I changed a weekly repeating event for one specific week through Noteplan on Mac. When I viewed the event later on my phone/watch, the original event appears as a daily repeating event. I don't know if it's a mix of using mobile and phone, some cache issues somewhere, or something else, but this is a fairly common use case for me. I don't have time to test it all but this is what I was able to do to reproduce.
Steps to reproduce:
  1. Create a weekly repeating event in Apple Calendar (Created on a Mac, used iCloud calendar)
  2. Pick one week to make a change just for that week (Noteplan for Mac)
  3. View the original repeating event and single changed event in iOS Calendar app, iOS Noteplan, Mac Noteplan and Mac Calendar
Expect:
  • all apps should show the change for just that week and the original repeating event every week except the changed event
Actual:
  • Mac noteplan show the change for just that week, no repeat on that day and the original repeating event is gone
  • Mac calendar shows a daily repeating event and the original repeating event is gone
  • iOS noteplan and iOS calendar shows the change for just that week, plus the original repeating event now repeats daily except the changed event as expected
I have some screenshots but I'm not able to attach them for some reason. Can share them elsewhere or try to attach later if it's possible.