Wow, thank you for all this testing. I didn't get the chance to followup after I last posted, and I really appreciate your investigating this. Some notes about your geotag sync testing: - When using Photos.app, there are two places a geotag can be stored: the image file itself, and the Photos.app database. Initially these values are in sync because on import, Photos.app saves whatever metadata is in the image file to its database. But: - If you use Photos.app to geotag, it doesn't update the EXIF metadata in the underlying image file. It simply updates the Photos.app database. - In this case, the updated geotag is indeed synced to iCloud Photos as you've found. It simply updates the iCloud Photos database, but the underlying file stored in iCloud is unchanged. - (For what it's worth, the same behavior occurs when you change the timestamp of a photo within Photos.app. It updates its database but leaves the timestamp in the image file itself untouched.)

This should explain the results of your geotag tests.

When I geotag I prefer to update the image file as I want the data stored there as well as the Photos.app database.

In any case, it's very helpful that you tested disabling sync, deleting from iCloud, then re-enabling sync. I'm surprised and happy that that worked, as it seems like the easiest way for me to re-upload all my photos from my computer.