I bought an upgrade to fc from IAD to LAX on Dec. 24. I bought it on the spot during a traditional check-in at IAD. Only 2 seats were left in fc. The reality is that I bought an upgrade and the seat next to me went empty. The flight left IAD after 20:00 and Y class was full. Since the flight left during dinner time, the dining service was very good and I got a nice nap afterwards on those comfy seats to boot. The $250 upgrade was worth every dollar for a transcon flight leaving at that time of day.