I've never really understood the point of achieving top-tier status on one airline and then starting to fly someone else (unless you really fly a lot of miles and can obtain and maintain top-tier on both). Why not stick with what you've got and use that status to your advantage?
Absolutely!!! I view it as a waste of time and money to get top-tier elite on one airline then move to another. "Well, I made 1K so that I can say I made 1K. But I don't want to use that to my advantage."
The OP might have a chance at making UGS if s/he sticks with UA.