A number of tickets were systematically routed from one agent back to the group. There aren't any triggers or automations responsible for the reassignments. None of my agents reassigned these tickets. Why were tickets randomly reassigned back to the group?
When you remove the current assignee from a group, the ticket maintains its group status.
If an agent is assigned tickets in a particular group and then removed from that group, those tickets are automatically reassigned back to the original group. In some cases, the admin removed the original assignee from that group.