Default A Delegate?

Summary: If someone is out of office and the employee neglected to set a delegate before going out, is it possible build a process to set a default delegate in their absence?

Content (required): We have some employees that are going on leave and not setting a delegate before they go out on PTO. This is causing delays in getting requisitions and offers approved. We're hoping to be able to build an automatic process to set the delegate rather than having to update each record manually. We have enough cases that this is becoming difficult to keep up with manually.