Calendar event updates were lost

Sometime during the last week all of the event changes I made to existing events in the stake calendar reverted back to their pre-change settings and descriptions. It's like the calendar had been "restored" to a date prior to my changes. Any ideas?

Let's retire this question. I need to do some deeper research. I don't want to raise an alert until I know for certain about the problem. Sorry for jumping the gun with this. Feel free to delete the original message.