Sailingfun, I'm not confident that your assessment this deal allows for arbitration is accurate. My understanding is that the companies would be "forced" merged if the DAL scope section was NOT given relief. Otherwise, why the relief? When DAL bought Comair, the contract had scope and the Comair MEC tried to initiated a PID. That went nowhere because it was not considered a merger.
I believe the same applies here, only the scope relief is for ac larger than the 76 seats permitted in the contract. The contract relief will allow for two separate operations. This is perhaps one of the few ways to get the deal announced and not put the DAL group in a forced situation. If the DAL MEC said no before to arbitration, then why risk it now after holding the keys to move this deal forward? The only thing that has changed is the speed at which forced arbitration would occur. Makes little sense.