Looks like I spoke too soon. I thought that process worked but actually did that for an activity last week and am just realizing it didn’t load. Might need @JamesChevalier’s input on this one.
I’ve got one from May 15th. There were multiple activities that day. I had a walk I forgot to stop, and ended up with a mile in the car. I trimmed, deleted, and resynched.
I wouldn’t really care in the grand scheme of things- but that activity helped push me to 100% completion of my town…
Another option is to do the editing in Garmin or other FIT file editor (fitfiletools), get the corrected FIT file on your computer/phone/local device, then delete on both Garmin and CS.
When you go back into garmin connect and upload the corrected FIT file it will push the “new” activity to CS
As for what’s going on behind the scenes, Garmin notifies CityStrides of new activities (this includes all info I need, outside of privacy info for some reason)
Old activity syncing works where CityStrides sends a request that asks for activities within a certain time frame & Garmin acknowledges the request then sends notifications for those activities as if they had just happened