My friend is on all United flights First class award trip from the US to Asia. He's actually in Asia right now and something odd happened to his return flights back to the US. He booked the flights few months ago and had confirmed First Class seats on all his flights. Today, he checked his itinerary on United.com and all of sudden his seating assignment from SFO-IAD on 763 is gone!(In fact, his PVG-SFO hasn't been touched) He called United in the US and United rep and her supervisor both said, "the corporate took the seat" and the best thing they can do is put him on next flight which is two hours later. Anyhoo, the point is United took my friend's first class seat assignment and didn't notify him and left him hanging. They booked him on C class on the same flight. He is on UA 872 on 1/2.

So, what kind of compensation should he get from United? Please share your opinion. Thanks guys.