SkyWest does not own the UAL flying. They service a contract for UAL. If SkyWest were to overplay their hand they could find UAL acquiring a different regional and taking away the Inc flying to boot leaving them with zip. Selling could put them in a position with servicing UAL flying for several years.
I think the majors have made it clear they want most of the regional flying in-house with just a few major players such as Inc picking up slack. I think there will be some major shakeups over the next few months. Some pilots chasing the upgrades may find they reached for the wrong brass ring.