From what I've read, there's no indicated UP wants to give up its responsibilities. It's simply that UP wants Metra to operate the trains themselves, instead of having them use UP employees to run. So basically Metra is budgeting to have their own employees run the trains instead of Union Pacific. UP still owns the tracks, coordinates trains, etc.
https://www.up.com/media/statements/metra/index.htm
https://www.trains.com/trn/news-revi...muter-dispute/