AA owns all those ERJs. Why would they park them and sell for someone else to fly for a competitor? AA probably doesn't want that many ERJs flying, but if they can sublet them and get the job done a lower cost than Eagle cost them, then it's highly likely to happen. BTW Eagle will probably always cost more as long as its entirely operated inside AMR.
AA leases all of those ERJ's as far as I know.
Why sublet them(and be stuck at a high initial lease cost) when you can shed the leases(or DRASTICALLY reduce them) in the bankruptcy? I am sure AA will offer the lessor like 10% of what they are currently paying and if the lessor wont take it, they will just shed the lease and the lessor will be stuck with the plane. Seeing as how the market for used ERJ's isnt good right now, you might be surprised to see the lessor accept a crazy deal and Eagle will continue in its present form. I doubt this will happen, but it might.