2 days ago I signed out of my German Apple ID on my 2017 iMac running latest Monterey version 12.4 and signed in to my US Apple ID to downgrade the subscription of the iCloud storage.
Afterwards I signed back into my German Apple ID.
Yesterday I found out that my Mail signatures are gone. The Mail rules popped up after a while but the signatures are still gone today. I checked the settings in the various System Preferences to no avail.
Are the signatures buried somewhere in my backups (TimeMachine and/or Carbon Copy Cloner) ? 
It’s a miracle, the signatures are back after 2 days of waiting. Not sure how, but this process seems to be working way too long…
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