Caltopo stripping GPX

GPX files exported from WorkOutDoors / Apple Watch contain valid per-trackpoint time data, but after importing those GPX files into CalTopo and exporting them again, the trackpoint timestamps appear to be stripped or replaced with zero/epoch values.

I tested this with a WorkOutDoors GPX file that has valid <time> tags on every trackpoint. Example structure from the original GPX:

<trkpt lat="45.6658338" lon="-111.0232691">
  <time>2026-06-13T16:19:38.944Z</time>
  <extensions>
    ...
  </extensions>
</trkpt>

However, after importing the GPX into CalTopo the time data no longer appears usable:

• In Caltopo web app, profile shows timestamp of 12/31/1969, 5:00:00 PM GMT-07:00 for all points
• In GPX exported from Caltopo, the affected tracks show timestamps like 1970-01-01T00:00:00Z for every point.
• In exported GeoJSON, the coordinate arrays appear to include a fourth value for time, but it is set to 0, for example:
  [longitude, latitude, elevation, 0]

This makes it seems like CalTopo may be preserving the geometry but discarding or normalizing the original trackpoint timestamps during the import/export process.

I prefer to use WorkOutdoors to record tracks over the Caltopo app because it saves phone battery, and WO has great apple watch integration. But, I really need that data to cross reference start time, duration, etc of my tracks. Would it be possible to preserve time data from uploaded GPX tracks moving forward? Or, if there's something I'm doing wrong, please let me know!