If an alert is classified as "Unassigned" (no defined owner), then it will be repeatedly updated until an owner (other than 'Unassigned') is assigned.
Desired behavior:
If the alert has not been assigned to an owner (ie, it is "Unassigned") and there is no defined owner during the next update cycle, then just ignore (no update should be made).
hmscott4
commented
3 years ago 
If an alert is classified as "Unassigned" (no defined owner), then it will be repeatedly updated until an owner (other than 'Unassigned') is assigned.
Desired behavior: If the alert has not been assigned to an owner (ie, it is "Unassigned") and there is no defined owner during the next update cycle, then just ignore (no update should be made).