v8.1.47
Not sure there's much I can provide that will help to provide backups or logs to diagnose the cause for this one, but it's more a what-to-do if it happens to someone else.
I have 2x UDT definitions for a valve, one has open/close commands and the other doesn't (control valve), however reading the control valve's non-existent open or close tags returned "Error_Configuration" instead of "Bad_NotFound" which was messing with isAvailable's conditions and returning true instead of false.
To fix it, I had to add the two non-existent tags to the definition and then delete them again. Possibly it was some artifact from duplicating the other valve udt definition to create the one for the control valve 