In my opinion, US Airways will sell at least its PSA RJ operation and CRJ-200/700 delivery positions to Mesa for about $100 million. Then US Airways and Mesa will code share the operation and the deal would comply with J4J.
In regard to Piedmont and Allegheny, the companies are being downsized and management wants a minimum size turboprop operation to serve airports that cannot support a RJ. Thus, I believe these two companies may be merged with a competitive cost structure or one or both could be liquidated.
Regards,
USA320Pilot