As far as the mesa thing goes: I'm not sure if were hiring straight into the left seat of the dash anymore. Lots of recent hiring will result in upgrades for those already here. Not positive about that though.

Yes, the JFK thing is going away, but per the contract, they have to offer you a seat in the airplane that is replacing what you fly or you can take a different domecile.

As far as Mesa out west : GJT is senior, but DEN and PHX are very holdable. As long as your not one of the bottom 5-7 guys, you wont be flying reserve.