Maybe the OP wants an eligible for rehire status for when he applies for another job down the road. I would be hard pressed to leave a company with the reputation that UPS has with the general public as a not eligible for rehire.
I fought this years ago with a Manager over a young guy who had worked for the company for 5 years during college. His last year he had some attendance issues due to requirements to fulfill his degree. He was leaving to get his Masters degree at another University out of state. Did not want to transfer. He just wanted to give his two weeks notice and leave with a favorable status.
We worked it out, and all was good.
If I was the OP I would go higher up the chain. What can it hurt?