I have posted a new version of GPS-Speedreader at github.com/prichterich/GPS-Speedreader that supports posting of Garmin 255 (and 255 Music) results to the GPS Team Challenge web site. Only results from .fit files that were recorded with the required settings (all GNSS systems + multiband, activity with minimal filtering) can be posted. This release also contains other improvements and bug fixes; more details are at github.com/prichterich/GPS-Speedreader/blob/main/CHANGELOG.md
If you plan to post results from the Garmin 255 watches to the GPS Team Challenge using GPS Speedreader, please update to this version. Older version may give incorrect results, in particular for the 5x10 second category, since they did not take some peculiarities in the Garmin data into account.
Some basic help is at github.com/prichterich/GPS-Speedreader/wiki/GPS-Speedreader-Help
Warning!
Apparently the 255 has it's antenna on the rim, wetsuit material next to the edge of the watch can ruin the satellite reception
This is enough to give bad readings, or none. Where the watch on top of any clothing, don't roll your sleeve up alongside the watch.
