They have no right to devaluate our hard earned miles like that - and I hope the United Million Miler case will prove that Frenquent FLyer program is a contract. The Judge in Chicago refused to dismiss the case just because there is the escape clause: "we can change anything and void everything anytime even without telling you".
Yes, they do. It's in the T&C's.
The UA MM suit was allowed to go forward with the explicit note that "defendants had a contract with Million Miler members which differed from the contract they had with other Mileage Plus members" as the program T&C disclaimer only referred to "MileagePlus membership and benefits, including the Premier Program, "
I'm pretty sure aware availability doesn't fall under a completely different contractual arrangement than the DM program. And I'm pretty sure those seats will be full, regardless of what any seatmap (which only bares a passing resemblance to tickets sold) says today.
But you can file another lawsuit and give it a shot.