Put your apps in where you want to be (Majors). Be prepared for a quick call from any regional. I was in a desk at the end of my career and went to XJT to get currency. It was fine and I now have a job offer with United. Don't worry about upgrade if you have a decent logbook with the AF. You probably have plenty of PIC time and upgrade at a regional will probably not happen because you will be at your "forever home" before you hit upgrade. I would have no reservations about XJT or SKW. Not so sure about TSA....