hiho,

have a look into table OO_TRIGGERS (OO_TRIGGERS.TRIGGER_TYPE = 'CRON') 

Regards Rene

If the OO DB is not purged correctly, it could cause orphaned rows in OO DB. When orphaned records are collected the procedure messages can be seen:
"Marked for deletion a total: (xxxxxx number) potentially orphaned rows from (a table name)."
In some cases the orphaned rows are only collected if there is space in the collection limit.
When the size of the OO DB keeps growing while OO DB purge procedure is performed regularly, and above message is seen, please open a support ticket to report the issue.  

hiho,

in this case I think it's more likely that the flows in the scheduler were imported with a new namespace (content pack update). As a result they disappear from the view in the scheduler but are not deleted in the database and then cause these messages because the flow no longer exists under that namespace. At least that's what we've seen a few times with CloudSlang.

Regards Rene