What would you say to an IT professional

[king1]

you do tend to rely on your email provider knowing what they're doing and by the sound of it there only 'fault', if there is one, is not having an ability to restore from backup, but that's been the case forever with most if not all email providers.

But I would say where he seriously went wrong was in doing a 'move' operation rather than a 'copy' - regardless of source/destination, if it's important stuff I will always copy first, verify it arrived correctly, only then delete, or rename the folder old_xxxxxx.