I'd sit tight if I were you. Keep your head down till you're off probation, support your fellow pilots, don't do anything stupid like cross a picket line (if it comes to that) and wait for things to shake out. Seven months if halfway to upgrade there, from what it sounds like so you might as well tough it out. It worked out in the long run for Mesaba and I'm willing to bet the turbulence will pass at Pinnacle too. And so what if worse comes to worse and they shut the doors, send y'all packing and turn the airplanes into soda cans? At least it will be easier to explain to a future employer why you left

Just think of it like a bad relationship but the girl is smoking hot and a nympho to boot. She might be a pain the a$$ sometimes and yeah, its an emotional roller coaster but you're getting what you need (a paycheck and building time) without the emotional attachment.