So let's take a look at reality.so everyone leaves at the same time to deliver the mail and then anyone who comes back early will either do indoor work or go out and help others until it's official finish time.
Week 1:You send the early finishers back out.
This reduces your overtime and you think this is a wonderful idea.
Week 2: You have no early finishers.
Why would they rush around just to finish some other guy's delivery.
Your OT budget has gone through the roof again.
Week 3: You don't get much lapsing done.
You've removed a great deal of the motivation from the runners and even from the guys on the smaller deliveries, why would they, if they're going to hang out a duty until finish time they might as well go the whole way.
Now you have an OT problem and a busted lapsing plan.
Week 4: What do you think happens in week 4?