From c7320bf91fd8fd8cd5555b444078a430e2b512cb Mon Sep 17 00:00:00 2001
From: miles-grant-ibigroup <miles.grant@ibigroup.com>
Date: Mon, 27 Apr 2026 17:17:42 -0400
Subject: [PATCH 01/13] remove broken implementation

---
 .gitignore                                    |  4 ++-
 .../conveyal/gtfs/loader/JdbcTableWriter.java | 27 +++++--------------
 2 files changed, 10 insertions(+), 21 deletions(-)

diff --git a/.gitignore b/.gitignore
index dc693fe79..7a707e02d 100644
--- a/.gitignore
+++ b/.gitignore
@@ -9,4 +9,6 @@
 .idea/
 target/
 
-lambda$*.json
\ No newline at end of file
+lambda$*.json
+
+.DS_Store
\ No newline at end of file
diff --git a/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java b/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java
index f7300661d..4771bbf22 100644
--- a/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java
+++ b/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java
@@ -854,7 +854,6 @@ private int updateStopTimesForPatternStops(List<PatternStop> patternStops, boole
         for (String tripId : timesForTripIds.keySet()) {
             // Initialize travel time with previous stop time value.
             int cumulativeTravelTime = timesForTripIds.get(tripId);
-            int cumulativeInterpolatedTime = cumulativeTravelTime;
             int timepointNumber = 0;
             double previousShapeDistTraveled = 0; // Used for calculating timepoint speed for interpolation
             for (PatternStop patternStop : patternStops) {
@@ -870,26 +869,14 @@ private int updateStopTimesForPatternStops(List<PatternStop> patternStops, boole
                     if (!isTimepoint) travelTime = interpolateTimesFromTimepoints(patternStop, timepoints, timepointNumber, previousShapeDistTraveled);
                     previousShapeDistTraveled += patternStop.shape_dist_traveled;
                 }
-                int dwellTime = patternStop.default_dwell_time == Entity.INT_MISSING ? 0 : patternStop.default_dwell_time;
-                int oneBasedIndex = 1;
+                int dwellTime = patternStop.default_dwell_time == Entity.INT_MISSING || interpolateStopTimes ? 0 : patternStop.default_dwell_time;
                 // Increase travel time by current pattern stop's travel and dwell times (and set values for update).
-                if (!isTimepoint && interpolateStopTimes) {
-                    // We don't want to increment the true cumulative travel time because that adjusts the timepoint
-                    // times later in the pattern.
-                    // Dwell times are ignored right now as they do not fit the typical use case for interpolation.
-                    // They may be incorporated by accounting for all dwell times in intermediate stops when calculating
-                    // the timepoint speed.
-                    cumulativeInterpolatedTime += travelTime;
-                    updateStopTimeStatement.setInt(oneBasedIndex++, cumulativeInterpolatedTime);
-                    updateStopTimeStatement.setInt(oneBasedIndex++, cumulativeInterpolatedTime);
-                } else {
-                    cumulativeTravelTime += travelTime;
-                    updateStopTimeStatement.setInt(oneBasedIndex++, cumulativeTravelTime);
-                    cumulativeTravelTime += dwellTime;
-                    updateStopTimeStatement.setInt(oneBasedIndex++, cumulativeTravelTime);
-                }
-                updateStopTimeStatement.setString(oneBasedIndex++, tripId);
-                updateStopTimeStatement.setInt(oneBasedIndex++, patternStop.stop_sequence);
+                cumulativeTravelTime += travelTime;
+                updateStopTimeStatement.setInt(1, cumulativeTravelTime);
+                cumulativeTravelTime += dwellTime;
+                updateStopTimeStatement.setInt(2, cumulativeTravelTime);
+                updateStopTimeStatement.setString(3, tripId);
+                updateStopTimeStatement.setInt(4, patternStop.stop_sequence);
                 stopTimesTracker.addBatch();
             }
         }

From 26eeafde727f7383d3da88744de19c339e336617 Mon Sep 17 00:00:00 2001
From: miles-grant-ibigroup <miles.grant@ibigroup.com>
Date: Mon, 27 Apr 2026 17:26:52 -0400
Subject: [PATCH 02/13] correct math

---
 src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java b/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java
index 4771bbf22..ec87767f6 100644
--- a/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java
+++ b/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java
@@ -806,7 +806,7 @@ private int interpolateTimesFromTimepoints(
         }
 
         double timepointSpeed = (nextTimepoint.shape_dist_traveled - lastTimepoint.shape_dist_traveled) / nextTimepoint.default_travel_time;
-        return (int) Math.round((patternStop.shape_dist_traveled - previousShapeDistTraveled) / timepointSpeed);
+        return (int) Math.round(Math.abs(patternStop.shape_dist_traveled - lastTimepoint.shape_dist_traveled) / timepointSpeed);
     }
 
     /**

From ad78a7ff568ca344bfaf8534cda1b38e6a890eba Mon Sep 17 00:00:00 2001
From: miles-grant-ibigroup <miles.grant@ibigroup.com>
Date: Mon, 27 Apr 2026 17:41:03 -0400
Subject: [PATCH 03/13] protect timepoint times

---
 src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java b/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java
index ec87767f6..1033533a6 100644
--- a/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java
+++ b/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java
@@ -870,6 +870,12 @@ private int updateStopTimesForPatternStops(List<PatternStop> patternStops, boole
                     previousShapeDistTraveled += patternStop.shape_dist_traveled;
                 }
                 int dwellTime = patternStop.default_dwell_time == Entity.INT_MISSING || interpolateStopTimes ? 0 : patternStop.default_dwell_time;
+
+                // In interpolation mode, don't write changes to db for timepoints
+                if (interpolateStopTimes && isTimepoint) {
+                    cumulativeTravelTime = cumulativeTravelTime + travelTime + dwellTime;
+                    continue;
+                }
                 // Increase travel time by current pattern stop's travel and dwell times (and set values for update).
                 cumulativeTravelTime += travelTime;
                 updateStopTimeStatement.setInt(1, cumulativeTravelTime);

From 91c58993b96411fffe9af6e3041fb1821ab2e366 Mon Sep 17 00:00:00 2001
From: miles-grant-ibigroup <miles.grant@ibigroup.com>
Date: Mon, 27 Apr 2026 17:48:00 -0400
Subject: [PATCH 04/13] correct even more math

---
 .../java/com/conveyal/gtfs/loader/JdbcTableWriter.java   | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java b/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java
index 1033533a6..13b7839ec 100644
--- a/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java
+++ b/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java
@@ -787,8 +787,7 @@ private int updateStopTimesForPatternStop(ObjectNode patternStop, int previousTr
     private int interpolateTimesFromTimepoints(
         PatternStop patternStop,
         List<PatternStop> timepoints,
-        Integer timepointNumber,
-        double previousShapeDistTraveled
+        Integer timepointNumber
     ) {
         if (timepointNumber == 0 || timepoints.size() == 1 || timepointNumber >= timepoints.size()) {
             throw new IllegalStateException("Issue in pattern stops which prevents interpolation (e.g. less than 2 timepoints)");
@@ -805,7 +804,7 @@ private int interpolateTimesFromTimepoints(
             throw new IllegalStateException("Error with stop time interpolation: timepoint or shape_dist_traveled is null");
         }
 
-        double timepointSpeed = (nextTimepoint.shape_dist_traveled - lastTimepoint.shape_dist_traveled) / nextTimepoint.default_travel_time;
+        double timepointSpeed = nextTimepoint.shape_dist_traveled / nextTimepoint.default_travel_time;
         return (int) Math.round(Math.abs(patternStop.shape_dist_traveled - lastTimepoint.shape_dist_traveled) / timepointSpeed);
     }
 
@@ -855,7 +854,6 @@ private int updateStopTimesForPatternStops(List<PatternStop> patternStops, boole
             // Initialize travel time with previous stop time value.
             int cumulativeTravelTime = timesForTripIds.get(tripId);
             int timepointNumber = 0;
-            double previousShapeDistTraveled = 0; // Used for calculating timepoint speed for interpolation
             for (PatternStop patternStop : patternStops) {
                 boolean isTimepoint = patternStop.timepoint == 1;
                 if (isTimepoint) timepointNumber++;
@@ -866,8 +864,7 @@ private int updateStopTimesForPatternStops(List<PatternStop> patternStops, boole
                         throw new IllegalStateException("Shape_dist_traveled must be defined for all stops in order to perform interpolation");
                     }
                     // Override travel time if we're interpolating between timepoints.
-                    if (!isTimepoint) travelTime = interpolateTimesFromTimepoints(patternStop, timepoints, timepointNumber, previousShapeDistTraveled);
-                    previousShapeDistTraveled += patternStop.shape_dist_traveled;
+                    if (!isTimepoint) travelTime = interpolateTimesFromTimepoints(patternStop, timepoints, timepointNumber);
                 }
                 int dwellTime = patternStop.default_dwell_time == Entity.INT_MISSING || interpolateStopTimes ? 0 : patternStop.default_dwell_time;
 

From 8deeea98d14212b14a63c351a332716a83f7de79 Mon Sep 17 00:00:00 2001
From: miles-grant-ibigroup <miles.grant@ibigroup.com>
Date: Mon, 27 Apr 2026 18:01:16 -0400
Subject: [PATCH 05/13] tweak timepoint interpolation math

---
 .../java/com/conveyal/gtfs/loader/JdbcTableWriter.java    | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java b/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java
index 13b7839ec..7fc40981f 100644
--- a/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java
+++ b/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java
@@ -793,19 +793,19 @@ private int interpolateTimesFromTimepoints(
             throw new IllegalStateException("Issue in pattern stops which prevents interpolation (e.g. less than 2 timepoints)");
         }
         PatternStop nextTimepoint = timepoints.get(timepointNumber);
-        PatternStop lastTimepoint = timepoints.get(timepointNumber-1);
+        PatternStop prevTimepoint = timepoints.get(timepointNumber-1);
 
         if (
             nextTimepoint == null ||
             nextTimepoint.default_travel_time == Entity.INT_MISSING ||
             nextTimepoint.shape_dist_traveled == Entity.DOUBLE_MISSING ||
-            lastTimepoint.shape_dist_traveled == Entity.DOUBLE_MISSING
+            prevTimepoint.shape_dist_traveled == Entity.DOUBLE_MISSING
         ) {
             throw new IllegalStateException("Error with stop time interpolation: timepoint or shape_dist_traveled is null");
         }
 
-        double timepointSpeed = nextTimepoint.shape_dist_traveled / nextTimepoint.default_travel_time;
-        return (int) Math.round(Math.abs(patternStop.shape_dist_traveled - lastTimepoint.shape_dist_traveled) / timepointSpeed);
+        double timepointSpeed = (nextTimepoint.shape_dist_traveled - prevTimepoint.shape_dist_traveled) / nextTimepoint.default_travel_time;
+        return (int) Math.round(patternStop.shape_dist_traveled / timepointSpeed);
     }
 
     /**

From 9eb127bfc915bfef0e08efd4a5bcc7b60a2d9de7 Mon Sep 17 00:00:00 2001
From: miles-grant-ibigroup <miles.grant@ibigroup.com>
Date: Mon, 27 Apr 2026 18:08:41 -0400
Subject: [PATCH 06/13] simplify interpolation math

---
 src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java b/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java
index 7fc40981f..a05742668 100644
--- a/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java
+++ b/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java
@@ -804,7 +804,8 @@ private int interpolateTimesFromTimepoints(
             throw new IllegalStateException("Error with stop time interpolation: timepoint or shape_dist_traveled is null");
         }
 
-        double timepointSpeed = (nextTimepoint.shape_dist_traveled - prevTimepoint.shape_dist_traveled) / nextTimepoint.default_travel_time;
+        // TODO: average with the previous timepoint's time?
+        double timepointSpeed = nextTimepoint.shape_dist_traveled / nextTimepoint.default_travel_time;
         return (int) Math.round(patternStop.shape_dist_traveled / timepointSpeed);
     }
 

From fa9767f044572e2d5c75fb737c9880e0fce208f3 Mon Sep 17 00:00:00 2001
From: miles-grant-ibigroup <miles.grant@ibigroup.com>
Date: Tue, 28 Apr 2026 09:54:26 -0400
Subject: [PATCH 07/13] correct interpolation behavior

---
 .../conveyal/gtfs/loader/JdbcTableWriter.java | 28 +++++++++++++------
 1 file changed, 19 insertions(+), 9 deletions(-)

diff --git a/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java b/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java
index a05742668..3826b4e50 100644
--- a/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java
+++ b/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java
@@ -787,7 +787,8 @@ private int updateStopTimesForPatternStop(ObjectNode patternStop, int previousTr
     private int interpolateTimesFromTimepoints(
         PatternStop patternStop,
         List<PatternStop> timepoints,
-        Integer timepointNumber
+        Integer timepointNumber,
+        PatternStop prevPatternStop
     ) {
         if (timepointNumber == 0 || timepoints.size() == 1 || timepointNumber >= timepoints.size()) {
             throw new IllegalStateException("Issue in pattern stops which prevents interpolation (e.g. less than 2 timepoints)");
@@ -799,14 +800,16 @@ private int interpolateTimesFromTimepoints(
             nextTimepoint == null ||
             nextTimepoint.default_travel_time == Entity.INT_MISSING ||
             nextTimepoint.shape_dist_traveled == Entity.DOUBLE_MISSING ||
-            prevTimepoint.shape_dist_traveled == Entity.DOUBLE_MISSING
+            prevTimepoint.shape_dist_traveled == Entity.DOUBLE_MISSING ||
+            (prevPatternStop != null && prevPatternStop.shape_dist_traveled == Entity.DOUBLE_MISSING)
         ) {
             throw new IllegalStateException("Error with stop time interpolation: timepoint or shape_dist_traveled is null");
         }
 
-        // TODO: average with the previous timepoint's time?
-        double timepointSpeed = nextTimepoint.shape_dist_traveled / nextTimepoint.default_travel_time;
-        return (int) Math.round(patternStop.shape_dist_traveled / timepointSpeed);
+        double prevSdt = prevPatternStop == null ? 0 : prevPatternStop.shape_dist_traveled;
+
+        double timepointSpeed = (nextTimepoint.shape_dist_traveled - prevTimepoint.shape_dist_traveled) / nextTimepoint.default_travel_time;
+        return (int) Math.round((patternStop.shape_dist_traveled - prevSdt) / timepointSpeed);
     }
 
     /**
@@ -854,7 +857,9 @@ private int updateStopTimesForPatternStops(List<PatternStop> patternStops, boole
         for (String tripId : timesForTripIds.keySet()) {
             // Initialize travel time with previous stop time value.
             int cumulativeTravelTime = timesForTripIds.get(tripId);
+            int timepointCumulativeTravelTime = cumulativeTravelTime;
             int timepointNumber = 0;
+            PatternStop prevPatternStop = null;
             for (PatternStop patternStop : patternStops) {
                 boolean isTimepoint = patternStop.timepoint == 1;
                 if (isTimepoint) timepointNumber++;
@@ -865,13 +870,16 @@ private int updateStopTimesForPatternStops(List<PatternStop> patternStops, boole
                         throw new IllegalStateException("Shape_dist_traveled must be defined for all stops in order to perform interpolation");
                     }
                     // Override travel time if we're interpolating between timepoints.
-                    if (!isTimepoint) travelTime = interpolateTimesFromTimepoints(patternStop, timepoints, timepointNumber);
+                    if (!isTimepoint) travelTime = interpolateTimesFromTimepoints(patternStop, timepoints, timepointNumber, prevPatternStop);
                 }
-                int dwellTime = patternStop.default_dwell_time == Entity.INT_MISSING || interpolateStopTimes ? 0 : patternStop.default_dwell_time;
+                int dwellTime = patternStop.default_dwell_time == Entity.INT_MISSING || (interpolateStopTimes && !isTimepoint) ? 0 : patternStop.default_dwell_time;
 
                 // In interpolation mode, don't write changes to db for timepoints
+                // We don't write the travel time, since it is interpolated
                 if (interpolateStopTimes && isTimepoint) {
-                    cumulativeTravelTime = cumulativeTravelTime + travelTime + dwellTime;
+                    timepointCumulativeTravelTime = timepointCumulativeTravelTime + travelTime + dwellTime;
+                    // Reset the cumulativeTravelTime to the schedule truth
+                    cumulativeTravelTime = timepointCumulativeTravelTime;
                     continue;
                 }
                 // Increase travel time by current pattern stop's travel and dwell times (and set values for update).
@@ -882,6 +890,8 @@ private int updateStopTimesForPatternStops(List<PatternStop> patternStops, boole
                 updateStopTimeStatement.setString(3, tripId);
                 updateStopTimeStatement.setInt(4, patternStop.stop_sequence);
                 stopTimesTracker.addBatch();
+                
+                prevPatternStop = patternStop;
             }
         }
         return stopTimesTracker.executeRemaining();
@@ -1612,7 +1622,7 @@ private String[] parseExceptionListField(int id, String namespace, Table table,
         return parsedString.replaceAll("[{}]", "").split("[,]", 0);
     }
 
-    private String getResultSetString(int column, ResultSet resultSet) throws java.sql.SQLException {
+    private String getResultSetString(int column, ResultSet resultSet) throws SQLException {
         String resultSetString = resultSet.getString(column);
         return resultSetString == null ? "" : resultSetString;
     }

From c55925cc3f518a1f2691190612b2642dec2e68ef Mon Sep 17 00:00:00 2001
From: miles-grant-ibigroup <miles.grant@ibigroup.com>
Date: Mon, 4 May 2026 12:31:05 -0400
Subject: [PATCH 08/13] support non-blank stoptime ignore

---
 .../conveyal/gtfs/loader/JdbcTableWriter.java | 49 ++++++++++++++++---
 1 file changed, 43 insertions(+), 6 deletions(-)

diff --git a/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java b/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java
index 3826b4e50..90fd66728 100644
--- a/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java
+++ b/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java
@@ -262,7 +262,7 @@ public String update(Integer id, String json, boolean autoCommit) throws SQLExce
      * false for interpolation.
      */
     public int normalizeStopTimesForPattern(int id, int beginWithSequence) throws SQLException {
-        return normalizeStopTimesForPattern(id, beginWithSequence, false);
+        return normalizeStopTimesForPattern(id, beginWithSequence, false, false);
     }
 
     /**
@@ -271,7 +271,7 @@ public int normalizeStopTimesForPattern(int id, int beginWithSequence) throws SQ
      *
      * @return number of stop times updated
      */
-    public int normalizeStopTimesForPattern(int id, int beginWithSequence, boolean interpolateStopTimes) throws SQLException {
+    public int normalizeStopTimesForPattern(int id, int beginWithSequence, boolean interpolateStopTimes, boolean ignoreNonBlankStopTimes) throws SQLException {
         try {
             JDBCTableReader<PatternStop> patternStops = new JDBCTableReader(
                 Table.PATTERN_STOP,
@@ -288,7 +288,7 @@ public int normalizeStopTimesForPattern(int id, int beginWithSequence, boolean i
                     patternStopsToNormalize.add(patternStop);
                 }
             }
-            int stopTimesUpdated = updateStopTimesForPatternStops(patternStopsToNormalize, interpolateStopTimes);
+            int stopTimesUpdated = updateStopTimesForPatternStops(patternStopsToNormalize, interpolateStopTimes, ignoreNonBlankStopTimes);
             connection.commit();
             return stopTimesUpdated;
         } catch (Exception e) {
@@ -812,6 +812,22 @@ private int interpolateTimesFromTimepoints(
         return (int) Math.round((patternStop.shape_dist_traveled - prevSdt) / timepointSpeed);
     }
 
+    private boolean checkIfArrivalTimeExists(int stopSequence, String trip_id) throws SQLException {
+        String sql = String.format(
+                "select st.trip_id, arrival_time from %s.stop_times st where stop_sequence = ? " +
+                        "and st.trip_id = ?",
+                tablePrefix
+        );
+        PreparedStatement statement = connection.prepareStatement(sql);
+        statement.setInt(1, stopSequence);
+        statement.setString(2, trip_id);
+        ResultSet resultSet = statement.executeQuery();
+        while (resultSet.next()) {
+            int arrivalTime = resultSet.getInt(2);
+            if (arrivalTime <= 0) return false;
+        }
+        return true;
+    }
     /**
      * Normalizes all stop times' arrivals and departures for an ordered set of pattern stops. This set can be the full
      * set of stops for a pattern or just a subset. Typical usage for this method would be to overwrite the arrival and
@@ -821,8 +837,9 @@ private int interpolateTimesFromTimepoints(
      * @throws SQLException
      *
      * TODO? add param Set<String> serviceIdFilters service_id values to filter trips on
+     * TODO: Simply logic, avoid use of continue
      */
-    private int updateStopTimesForPatternStops(List<PatternStop> patternStops, boolean interpolateStopTimes) throws SQLException {
+    private int updateStopTimesForPatternStops(List<PatternStop> patternStops, boolean interpolateStopTimes, boolean ignoreNonBlankStopTimes) throws SQLException {
         PatternStop firstPatternStop = patternStops.iterator().next();
         List<PatternStop> timepoints = patternStops.stream().filter(ps -> ps.timepoint == 1).collect(Collectors.toList());
         int firstStopSequence = firstPatternStop.stop_sequence;
@@ -863,23 +880,43 @@ private int updateStopTimesForPatternStops(List<PatternStop> patternStops, boole
             for (PatternStop patternStop : patternStops) {
                 boolean isTimepoint = patternStop.timepoint == 1;
                 if (isTimepoint) timepointNumber++;
+                boolean hasStopTime = ignoreNonBlankStopTimes ? checkIfArrivalTimeExists(patternStop.stop_sequence, tripId) : true;
                 // Gather travel/dwell time for pattern stop (being sure to check for missing values).
                 int travelTime = patternStop.default_travel_time == Entity.INT_MISSING ? 0 : patternStop.default_travel_time;
-                if (interpolateStopTimes) {
+                if (interpolateStopTimes || ignoreNonBlankStopTimes) {
                     if (patternStop.shape_dist_traveled == Entity.DOUBLE_MISSING) {
                         throw new IllegalStateException("Shape_dist_traveled must be defined for all stops in order to perform interpolation");
                     }
                     // Override travel time if we're interpolating between timepoints.
-                    if (!isTimepoint) travelTime = interpolateTimesFromTimepoints(patternStop, timepoints, timepointNumber, prevPatternStop);
+                    if (!isTimepoint && !ignoreNonBlankStopTimes) travelTime = interpolateTimesFromTimepoints(patternStop, timepoints, timepointNumber, prevPatternStop);
+
+                    if (ignoreNonBlankStopTimes && !hasStopTime &&patternStop.stop_sequence != 0) travelTime = interpolateTimesFromTimepoints(patternStop, timepoints, timepointNumber, prevPatternStop);
                 }
                 int dwellTime = patternStop.default_dwell_time == Entity.INT_MISSING || (interpolateStopTimes && !isTimepoint) ? 0 : patternStop.default_dwell_time;
 
+                // In non-blank stop time mode, only update if our stoptime is blank
+                if (ignoreNonBlankStopTimes) {
+                    if (hasStopTime) {
+                        cumulativeTravelTime = cumulativeTravelTime + travelTime + dwellTime;
+                        prevPatternStop = patternStop;
+                        continue;
+                    }
+
+                    updateStopTimeStatement.setInt(1, cumulativeTravelTime + travelTime);
+                    updateStopTimeStatement.setInt(2, cumulativeTravelTime + travelTime);
+                    updateStopTimeStatement.setString(3, tripId);
+                    updateStopTimeStatement.setInt(4, patternStop.stop_sequence);
+                    stopTimesTracker.addBatch();
+                }
+
+
                 // In interpolation mode, don't write changes to db for timepoints
                 // We don't write the travel time, since it is interpolated
                 if (interpolateStopTimes && isTimepoint) {
                     timepointCumulativeTravelTime = timepointCumulativeTravelTime + travelTime + dwellTime;
                     // Reset the cumulativeTravelTime to the schedule truth
                     cumulativeTravelTime = timepointCumulativeTravelTime;
+                    prevPatternStop = patternStop;
                     continue;
                 }
                 // Increase travel time by current pattern stop's travel and dwell times (and set values for update).

From bf392d854df302f323a6c23d90660637c1abf4a1 Mon Sep 17 00:00:00 2001
From: miles-grant-ibigroup <miles.grant@ibigroup.com>
Date: Mon, 4 May 2026 12:34:46 -0400
Subject: [PATCH 09/13] update tests for new method signature

---
 src/test/java/com/conveyal/gtfs/loader/JDBCTableWriterTest.java | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/test/java/com/conveyal/gtfs/loader/JDBCTableWriterTest.java b/src/test/java/com/conveyal/gtfs/loader/JDBCTableWriterTest.java
index 171278a18..f5d949e66 100644
--- a/src/test/java/com/conveyal/gtfs/loader/JDBCTableWriterTest.java
+++ b/src/test/java/com/conveyal/gtfs/loader/JDBCTableWriterTest.java
@@ -874,7 +874,7 @@ private static String normalizeStopsForPattern(
         LOG.info("Updated pattern output: {}", updatedPatternOutput);
         // Normalize stop times.
         JdbcTableWriter updateTripWriter = createTestTableWriter(tripsTable);
-        updateTripWriter.normalizeStopTimesForPattern(pattern.id, 0, interpolateStopTimes);
+        updateTripWriter.normalizeStopTimesForPattern(pattern.id, 0, interpolateStopTimes, false);
 
         return createdTrip.trip_id;
     }

From 63e84c6ce799c51628fd1d4cf48cd92a729a4de5 Mon Sep 17 00:00:00 2001
From: miles-grant-ibigroup <miles.grant@ibigroup.com>
Date: Thu, 7 May 2026 17:08:14 -0400
Subject: [PATCH 10/13] address pr feedback

---
 .../conveyal/gtfs/loader/JdbcTableWriter.java | 55 +++++++++----------
 1 file changed, 27 insertions(+), 28 deletions(-)

diff --git a/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java b/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java
index 90fd66728..ca86cc3da 100644
--- a/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java
+++ b/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java
@@ -257,13 +257,6 @@ public String update(Integer id, String json, boolean autoCommit) throws SQLExce
         }
     }
 
-    /**
-     * Deprecated method to normalize stop times before stop time interpolation. Defaults to
-     * false for interpolation.
-     */
-    public int normalizeStopTimesForPattern(int id, int beginWithSequence) throws SQLException {
-        return normalizeStopTimesForPattern(id, beginWithSequence, false, false);
-    }
 
     /**
      * For a given pattern id and starting stop sequence (inclusive), normalize all stop times to match the pattern
@@ -813,20 +806,21 @@ private int interpolateTimesFromTimepoints(
     }
 
     private boolean checkIfArrivalTimeExists(int stopSequence, String trip_id) throws SQLException {
-        String sql = String.format(
-                "select st.trip_id, arrival_time from %s.stop_times st where stop_sequence = ? " +
-                        "and st.trip_id = ?",
-                tablePrefix
-        );
+        String sql = String.format("select arrival_time from %s.stop_times where stop_sequence = ? " + "and trip_id = ?", tablePrefix);
         PreparedStatement statement = connection.prepareStatement(sql);
         statement.setInt(1, stopSequence);
         statement.setString(2, trip_id);
-        ResultSet resultSet = statement.executeQuery();
-        while (resultSet.next()) {
-            int arrivalTime = resultSet.getInt(2);
-            if (arrivalTime <= 0) return false;
+        try (ResultSet rs = statement.executeQuery()) {
+            if (!rs.next()) {
+                return false;
+            }
+            int arrivalTime = rs.getInt(1);
+            if (rs.wasNull()) {
+                return false;
+            }
+            return arrivalTime > 0;
         }
-        return true;
+
     }
     /**
      * Normalizes all stop times' arrivals and departures for an ordered set of pattern stops. This set can be the full
@@ -837,9 +831,12 @@ private boolean checkIfArrivalTimeExists(int stopSequence, String trip_id) throw
      * @throws SQLException
      *
      * TODO? add param Set<String> serviceIdFilters service_id values to filter trips on
-     * TODO: Simply logic, avoid use of continue
      */
-    private int updateStopTimesForPatternStops(List<PatternStop> patternStops, boolean interpolateStopTimes, boolean ignoreNonBlankStopTimes) throws SQLException {
+    private int updateStopTimesForPatternStops(
+            List<PatternStop> patternStops,
+            boolean interpolateStopTimes,
+            boolean ignoreNonBlankStopTimes
+    ) throws SQLException {
         PatternStop firstPatternStop = patternStops.iterator().next();
         List<PatternStop> timepoints = patternStops.stream().filter(ps -> ps.timepoint == 1).collect(Collectors.toList());
         int firstStopSequence = firstPatternStop.stop_sequence;
@@ -880,24 +877,26 @@ private int updateStopTimesForPatternStops(List<PatternStop> patternStops, boole
             for (PatternStop patternStop : patternStops) {
                 boolean isTimepoint = patternStop.timepoint == 1;
                 if (isTimepoint) timepointNumber++;
-                boolean hasStopTime = ignoreNonBlankStopTimes ? checkIfArrivalTimeExists(patternStop.stop_sequence, tripId) : true;
+                boolean hasStopTime = !ignoreNonBlankStopTimes || checkIfArrivalTimeExists(patternStop.stop_sequence, tripId);
                 // Gather travel/dwell time for pattern stop (being sure to check for missing values).
                 int travelTime = patternStop.default_travel_time == Entity.INT_MISSING ? 0 : patternStop.default_travel_time;
                 if (interpolateStopTimes || ignoreNonBlankStopTimes) {
                     if (patternStop.shape_dist_traveled == Entity.DOUBLE_MISSING) {
                         throw new IllegalStateException("Shape_dist_traveled must be defined for all stops in order to perform interpolation");
                     }
-                    // Override travel time if we're interpolating between timepoints.
-                    if (!isTimepoint && !ignoreNonBlankStopTimes) travelTime = interpolateTimesFromTimepoints(patternStop, timepoints, timepointNumber, prevPatternStop);
-
-                    if (ignoreNonBlankStopTimes && !hasStopTime &&patternStop.stop_sequence != 0) travelTime = interpolateTimesFromTimepoints(patternStop, timepoints, timepointNumber, prevPatternStop);
+                    // Override travel time if we're interpolating between timepoints, or generating blank stop times
+                    if ((!ignoreNonBlankStopTimes && !isTimepoint) || (ignoreNonBlankStopTimes && !hasStopTime && patternStop.stop_sequence != 0)) {
+                        travelTime = interpolateTimesFromTimepoints(patternStop, timepoints, timepointNumber, prevPatternStop);
+                    }
                 }
-                int dwellTime = patternStop.default_dwell_time == Entity.INT_MISSING || (interpolateStopTimes && !isTimepoint) ? 0 : patternStop.default_dwell_time;
+                // When interpolating, assume that *all* non-timepoint data is incorrect/missing
+                int dwellTime = patternStop.default_dwell_time == Entity.INT_MISSING || (interpolateStopTimes && !isTimepoint) ?
+                        0 : patternStop.default_dwell_time;
 
-                // In non-blank stop time mode, only update if our stoptime is blank
+                // In non-blank stop time mode, only update if our stop time is blank
                 if (ignoreNonBlankStopTimes) {
                     if (hasStopTime) {
-                        cumulativeTravelTime = cumulativeTravelTime + travelTime + dwellTime;
+                        cumulativeTravelTime += travelTime + dwellTime;
                         prevPatternStop = patternStop;
                         continue;
                     }
@@ -913,7 +912,7 @@ private int updateStopTimesForPatternStops(List<PatternStop> patternStops, boole
                 // In interpolation mode, don't write changes to db for timepoints
                 // We don't write the travel time, since it is interpolated
                 if (interpolateStopTimes && isTimepoint) {
-                    timepointCumulativeTravelTime = timepointCumulativeTravelTime + travelTime + dwellTime;
+                    timepointCumulativeTravelTime += travelTime + dwellTime;
                     // Reset the cumulativeTravelTime to the schedule truth
                     cumulativeTravelTime = timepointCumulativeTravelTime;
                     prevPatternStop = patternStop;

From 1240c3b099825a65e0cdf60466b06226111fc9d7 Mon Sep 17 00:00:00 2001
From: miles-grant-ibigroup <miles.grant@ibigroup.com>
Date: Tue, 26 May 2026 10:25:56 +0200
Subject: [PATCH 11/13] make error more helpful

---
 src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java b/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java
index ca86cc3da..f11c8e058 100644
--- a/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java
+++ b/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java
@@ -784,7 +784,7 @@ private int interpolateTimesFromTimepoints(
         PatternStop prevPatternStop
     ) {
         if (timepointNumber == 0 || timepoints.size() == 1 || timepointNumber >= timepoints.size()) {
-            throw new IllegalStateException("Issue in pattern stops which prevents interpolation (e.g. less than 2 timepoints)");
+            throw new IllegalStateException("Issue in pattern stops which prevents interpolation (e.g. less than 2 stoptimes to interpolate between)");
         }
         PatternStop nextTimepoint = timepoints.get(timepointNumber);
         PatternStop prevTimepoint = timepoints.get(timepointNumber-1);

From 0d08d7058123ebcadfe0a93cfc836f3f955777b2 Mon Sep 17 00:00:00 2001
From: miles-grant-ibigroup <miles.grant@ibigroup.com>
Date: Tue, 26 May 2026 16:26:45 +0200
Subject: [PATCH 12/13] add basic test for nonblank stoptime modification

---
 .../gtfs/loader/JDBCTableWriterTest.java      | 31 +++++++++++++++++++
 .../fake-agency-blank-stoptimes/agency.txt    |  2 ++
 .../fake-agency-blank-stoptimes/calendar.txt  |  2 ++
 .../fare_attributes.txt                       |  2 ++
 .../fare_rules.txt                            |  2 ++
 .../fake-agency-blank-stoptimes/routes.txt    |  2 ++
 .../fake-agency-blank-stoptimes/shapes.txt    |  3 ++
 .../stop_times.txt                            |  7 +++++
 .../fake-agency-blank-stoptimes/stops.txt     |  7 +++++
 .../fake-agency-blank-stoptimes/trips.txt     |  2 ++
 10 files changed, 60 insertions(+)
 create mode 100644 src/test/resources/fake-agency-blank-stoptimes/agency.txt
 create mode 100644 src/test/resources/fake-agency-blank-stoptimes/calendar.txt
 create mode 100644 src/test/resources/fake-agency-blank-stoptimes/fare_attributes.txt
 create mode 100644 src/test/resources/fake-agency-blank-stoptimes/fare_rules.txt
 create mode 100644 src/test/resources/fake-agency-blank-stoptimes/routes.txt
 create mode 100644 src/test/resources/fake-agency-blank-stoptimes/shapes.txt
 create mode 100644 src/test/resources/fake-agency-blank-stoptimes/stop_times.txt
 create mode 100644 src/test/resources/fake-agency-blank-stoptimes/stops.txt
 create mode 100644 src/test/resources/fake-agency-blank-stoptimes/trips.txt

diff --git a/src/test/java/com/conveyal/gtfs/loader/JDBCTableWriterTest.java b/src/test/java/com/conveyal/gtfs/loader/JDBCTableWriterTest.java
index f5d949e66..df2d2fc55 100644
--- a/src/test/java/com/conveyal/gtfs/loader/JDBCTableWriterTest.java
+++ b/src/test/java/com/conveyal/gtfs/loader/JDBCTableWriterTest.java
@@ -42,6 +42,7 @@
 import static com.conveyal.gtfs.TestUtils.getResourceFileName;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.equalTo;
+import static org.hamcrest.Matchers.greaterThan;
 import static org.hamcrest.Matchers.not;
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertNotEquals;
@@ -62,6 +63,7 @@ public class JDBCTableWriterTest {
     private static DataSource testDataSource;
     private static String testNamespace;
     private static String testGtfsGLSnapshotNamespace;
+    private static String testGtfsBlankStoptimesSnapshotNamespace;
     private static String simpleServiceId = "1";
     private static String firstStopId = "1";
     private static String secondStopId= "1.5";
@@ -109,6 +111,16 @@ public static void setUpClass() throws SQLException, IOException, InvalidNamespa
         JdbcGtfsSnapshotter snapshotter = new JdbcGtfsSnapshotter(testGtfsGLNamespace, testDataSource, false);
         SnapshotResult snapshotResult = snapshotter.copyTables();
         testGtfsGLSnapshotNamespace = snapshotResult.uniqueIdentifier;
+
+        // Load fake-agency-blank-stoptimes feed for use with blank stoptimes insertion test
+        FeedLoadResult blankStoptimesFeedLoadResult = load(TestUtils.zipFolderFiles("fake-agency-blank-stoptimes", true), testDataSource);
+        String testGtfsBlankStoptimesNamespace = blankStoptimesFeedLoadResult.uniqueIdentifier;
+        // validate feed to create additional tables
+        validate(testGtfsBlankStoptimesNamespace, testDataSource);
+        // load into editor via snapshot
+        JdbcGtfsSnapshotter blankStoptimesSnapshotter = new JdbcGtfsSnapshotter(testGtfsBlankStoptimesNamespace, testDataSource, false);
+        SnapshotResult blankStoptimesSnapshotResult = blankStoptimesSnapshotter.copyTables();
+        testGtfsBlankStoptimesSnapshotNamespace = blankStoptimesSnapshotResult.uniqueIdentifier;
     }
 
     @AfterAll
@@ -950,6 +962,25 @@ public void canNormalizePatternStopTimes() throws IOException, SQLException, Inv
         assertThat(index, equalTo(patternStops.length));
     }
 
+    @Test
+    public void canInterpolateMissingStoptimes() throws IOException, SQLException, InvalidNamespaceException {
+        JdbcTableWriter tableWriter = new JdbcTableWriter(Table.PATTERN_STOP, testDataSource, testGtfsBlankStoptimesSnapshotNamespace);
+        tableWriter.normalizeStopTimesForPattern(1, 0, false, true);
+
+        JDBCTableReader<StopTime> stopTimesTable = new JDBCTableReader(Table.STOP_TIMES,
+                testDataSource,
+                testGtfsBlankStoptimesSnapshotNamespace + ".",
+                EntityPopulator.STOP_TIME);
+        int index = 0;
+        for (StopTime stopTime : stopTimesTable.getOrdered("1720")) {
+            LOG.info("stop times i={} arrival={} departure={}", index, stopTime.arrival_time, stopTime.departure_time);
+            // These outcomes will be nonsensical, but correct given the nonsensical shape-dist-traveled values
+            assertThat(stopTime.arrival_time, greaterThan(0));
+            assertThat(stopTime.departure_time, greaterThan(0));
+            index++;
+        }
+    }
+
     /**
      * This test makes sure that updated the service_id will properly update affected referenced entities properly.
      * This test case was initially developed to prove that https://github.com/conveyal/gtfs-lib/issues/203 is
diff --git a/src/test/resources/fake-agency-blank-stoptimes/agency.txt b/src/test/resources/fake-agency-blank-stoptimes/agency.txt
new file mode 100644
index 000000000..b492e4aed
--- /dev/null
+++ b/src/test/resources/fake-agency-blank-stoptimes/agency.txt
@@ -0,0 +1,2 @@
+agency_id,agency_name,agency_url,agency_phone,agency_timezone,agency_lang
+1,"Tri Delta Transit","http://trideltatransit.com","(925) 754-4040","America/Los_Angeles","en"
diff --git a/src/test/resources/fake-agency-blank-stoptimes/calendar.txt b/src/test/resources/fake-agency-blank-stoptimes/calendar.txt
new file mode 100644
index 000000000..3de7f3950
--- /dev/null
+++ b/src/test/resources/fake-agency-blank-stoptimes/calendar.txt
@@ -0,0 +1,2 @@
+service_id,monday,tuesday,wednesday,thursday,friday,saturday,sunday,start_date,end_date
+1,1,1,1,1,1,1,1,20210828,20221231
diff --git a/src/test/resources/fake-agency-blank-stoptimes/fare_attributes.txt b/src/test/resources/fake-agency-blank-stoptimes/fare_attributes.txt
new file mode 100644
index 000000000..3db783ec3
--- /dev/null
+++ b/src/test/resources/fake-agency-blank-stoptimes/fare_attributes.txt
@@ -0,0 +1,2 @@
+fare_id,price,currency_type,payment_method,transfers,transfer_duration,agency_id
+"1",2.00,USD,0,0,,1
diff --git a/src/test/resources/fake-agency-blank-stoptimes/fare_rules.txt b/src/test/resources/fake-agency-blank-stoptimes/fare_rules.txt
new file mode 100644
index 000000000..33ebe9880
--- /dev/null
+++ b/src/test/resources/fake-agency-blank-stoptimes/fare_rules.txt
@@ -0,0 +1,2 @@
+fare_id,route_id
+"1","300"
diff --git a/src/test/resources/fake-agency-blank-stoptimes/routes.txt b/src/test/resources/fake-agency-blank-stoptimes/routes.txt
new file mode 100644
index 000000000..6c514bf35
--- /dev/null
+++ b/src/test/resources/fake-agency-blank-stoptimes/routes.txt
@@ -0,0 +1,2 @@
+route_id,agency_id,route_short_name,route_long_name,route_type,route_color,route_text_color,route_url
+"300",1,"300","Brentwood Park & Ride / Antioch BART",3,800080,FFFFFF,"http://12.155.17.20/RTT/Public/Schedule.aspx?RouteNo=300"
diff --git a/src/test/resources/fake-agency-blank-stoptimes/shapes.txt b/src/test/resources/fake-agency-blank-stoptimes/shapes.txt
new file mode 100644
index 000000000..cf8076634
--- /dev/null
+++ b/src/test/resources/fake-agency-blank-stoptimes/shapes.txt
@@ -0,0 +1,3 @@
+"shape_id","shape_pt_lon","shape_pt_lat","shape_pt_sequence","shape_dist_traveled"
+"27","-121.780946","37.996068","1","0"
+"27","-121.69877","37.933812","2","200"
\ No newline at end of file
diff --git a/src/test/resources/fake-agency-blank-stoptimes/stop_times.txt b/src/test/resources/fake-agency-blank-stoptimes/stop_times.txt
new file mode 100644
index 000000000..38d10131e
--- /dev/null
+++ b/src/test/resources/fake-agency-blank-stoptimes/stop_times.txt
@@ -0,0 +1,7 @@
+"trip_id","arrival_time","departure_time","stop_id","stop_sequence","stop_headsign","timepoint","shape_dist_traveled"
+"1720","17:46:00","17:46:00","722","0","","1","0"
+"1720","17:59:00","17:59:00","33","2","","1","50"
+"1720","","","900","3","","","150"
+"1720","18:02:01","18:02:01","443","4","","0","200"
+"1720","18:20:06","18:20:06","421","5","","0","250"
+"1720","18:24:00","18:24:00","610","6","","1","300"
\ No newline at end of file
diff --git a/src/test/resources/fake-agency-blank-stoptimes/stops.txt b/src/test/resources/fake-agency-blank-stoptimes/stops.txt
new file mode 100644
index 000000000..6fab93481
--- /dev/null
+++ b/src/test/resources/fake-agency-blank-stoptimes/stops.txt
@@ -0,0 +1,7 @@
+"stop_id","stop_code","stop_name","stop_lat","stop_lon","stop_url","zone_id"
+"33","813644","Main St & Empire Ave","37.997839","-121.730492","http://12.155.17.20/RTT/Public/RoutePositionET.aspx?PlatformTag=33",""
+"421","810930","Brentwood Blvd & Village Dr","37.941524","-121.696341","http://12.155.17.20/RTT/Public/RoutePositionET.aspx?PlatformTag=421",""
+"443","811043","Main St & Norcross Ln","37.997716","-121.716376","http://12.155.17.20/RTT/Public/RoutePositionET.aspx?PlatformTag=443",""
+"610","811425","Brentwood Park n Ride","37.933838","-121.698755","http://12.155.17.20/RTT/Public/RoutePositionET.aspx?PlatformTag=610",""
+"722","817754","Antioch BART","37.995572","-121.778137","http://12.155.17.20/RTT/Public/RoutePositionET.aspx?PlatformTag=722",""
+"900","817755","test statin","37.995578","-121.778139","",""
\ No newline at end of file
diff --git a/src/test/resources/fake-agency-blank-stoptimes/trips.txt b/src/test/resources/fake-agency-blank-stoptimes/trips.txt
new file mode 100644
index 000000000..9c50e4f5a
--- /dev/null
+++ b/src/test/resources/fake-agency-blank-stoptimes/trips.txt
@@ -0,0 +1,2 @@
+route_id,service_id,trip_id,trip_headsign,direction_id,block_id,shape_id
+"300",1,1720,"Eastbound Brentwood Park & Ride",0,167,27

From 489de791283fc6c9f6c40b48820dca1e7914ca63 Mon Sep 17 00:00:00 2001
From: miles-grant-ibigroup <miles.grant@ibigroup.com>
Date: Wed, 27 May 2026 11:41:33 +0200
Subject: [PATCH 13/13] address pr feedback

---
 src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java b/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java
index f11c8e058..cb02c57ff 100644
--- a/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java
+++ b/src/main/java/com/conveyal/gtfs/loader/JdbcTableWriter.java
@@ -787,7 +787,7 @@ private int interpolateTimesFromTimepoints(
             throw new IllegalStateException("Issue in pattern stops which prevents interpolation (e.g. less than 2 stoptimes to interpolate between)");
         }
         PatternStop nextTimepoint = timepoints.get(timepointNumber);
-        PatternStop prevTimepoint = timepoints.get(timepointNumber-1);
+        PatternStop prevTimepoint = timepoints.get(timepointNumber - 1);
 
         if (
             nextTimepoint == null ||
@@ -806,7 +806,7 @@ private int interpolateTimesFromTimepoints(
     }
 
     private boolean checkIfArrivalTimeExists(int stopSequence, String trip_id) throws SQLException {
-        String sql = String.format("select arrival_time from %s.stop_times where stop_sequence = ? " + "and trip_id = ?", tablePrefix);
+        String sql = String.format("select arrival_time from %s.stop_times where stop_sequence = ? and trip_id = ?", tablePrefix);
         PreparedStatement statement = connection.prepareStatement(sql);
         statement.setInt(1, stopSequence);
         statement.setString(2, trip_id);
@@ -890,6 +890,7 @@ private int updateStopTimesForPatternStops(
                     }
                 }
                 // When interpolating, assume that *all* non-timepoint data is incorrect/missing
+                // The travel and dwell times defined for stops between timepoints will be ignored.
                 int dwellTime = patternStop.default_dwell_time == Entity.INT_MISSING || (interpolateStopTimes && !isTimepoint) ?
                         0 : patternStop.default_dwell_time;