iPhone Calendar problem with iOS 17.1.1 update

I believe this is an issue with the way the iOS calendar app (or the underlying Apple framework) interfaces specifically with MS Exchange shared calendars. I have tested this with an iCloud shared calendar and the issue cannot be reproduced. So interfacing to iCloud mail/calendar servers is not a problem. It is not a Microsoft issue either, because I can't reproduce the issue with two Windows laptops working with the same shared Outlook calendar. Add to that the fact that the emergence of the problems coincided with the 17.x.x updates, and I would say the update (most likely 17.1.1) broke the MS Exchange interface.

One *temporary* workaround for new entries is to create a shared iCloud calendar and share across iCloud id's. It is easy to generate a free iCloud id from within an iOS device, if you don't have one. To share the same calendar across Windows devices running Outlook you will need to add the iCloud account to Outlook, and supply your password (or a generated application password if you have MFA enabled). A bit more involved, but doable.

I insist that this be a temporary step until a fix is pushed out, because I do not want to bear the burden of replicating all legacy calendar entries from the Microsoft calendar to the new Apple one, and abandon the old calendar. I have a need for shared calendars to reside on MS Exchange. When the problem is fixed I will abandon the Apple shared calendar and go back to the Exchange calendar.