The 145s and 200s will dwindle down even at low oil prices they are
Talking about it, see USA today for article that's about 300/360 aircraft for expressjet and there's no plans that I've ever heard of for 175s to go there. So if there's no demand for your supply what do you do?

I think expressjet pilots would probably find a home at Skywest one way or another but I don't think the planes will