Requisition Approval notifications - reassign v delegate from worklist

Summary:

Can a user who has access to a shared worklist view, reassign notifications and the associated authority

Content (required):

in our requisition approval rules, there is a header stage (first responder wins) where we route to an individual (Joan Smith) as they are the focal point for the team. Joan has a view setup in BPM so that team managers can see all of her worklist. The managers then reassign the worklist to team members to check / edit requisitions

We are finding that if Joan reassigns or delegates, then the approval of this stage is successful (if the team member subsequently edits the requisition). However, if one of the team managers reassigns the notification, then it loops back round to Joan Smith after edit. We can see that it is using the approval rule to route back to Joan, but unsure why if it has been reassgined by a colleague it is not being treated in the same way