Google Calendar sync

The google calendar sync doesnt work as expected. Sometimes the event get’s a new “start’s on” time. It looks like the new start’s on time is the sync time from the scheduled job.

The new event was saved days before. An for some reason the event from yesterday (06.09.2021 18:30) was changed today at 9 am.
Any ideas?
BR Paul

I have found an indication of what is happening:

There is a workaround, but not a solution (yet).