Can not remove shield from sheet, AC changes reverting.

Thanks for your report! As Gauss mentioned, there have been several reports for issues similar to what you've reported. We've been able to diagnose what we believe is the root cause, and Devs are currently working on a fix for release asap. We expect this to resolve your issue, but it's possible there are more than one cause for a similar experience. When the fix is out, I or someone will come back here to let you know.

We've pushed this update to production that I believe will resolve the issue with the changes you made being undone. There is some additional work that will be done in the near term to further optimize the synchronization of data being sent from multiple users. It is possible that your specific issue wasn't due to this problem, so if you experience the undoing again, please let me know here.