Remember when UAL was going through bankruptcy and was trying to shed the AWAC contract? AWAC made a deal on the side with US Airways using the the escrow money that was slated for United had they resigned, and told United to F-off.
Not only did they secure a vastly better deal with Airways, the owners made about $300 mil off their stock allotment.
I'm guessing something similar happened again. AWAC went to Delta, word got out to Airways/AA, and they said "whoa whoa hold on, let's not get crazy" and gave AWAC an offer that was vastly better than Delta's. Hence why AWAC then told Delta to F-off, which is just awesome BTW.