I've noticed a recent separation of class paid/flown. If you receive an upgrade and your flight is disrupted, when you try to re-book you are only shown flights based on the class paid - which means no matter what you do, you will not retain your upgrade and be placed back into the upgrade que if seats are available. Prior to the class paid/flown seperation, if you were upgraded and your flight was disrupted, the search would look for other flights in first so you could keep your upgrade.

Not sure if it this is a bug or intentional programming, but it really hurts when there are flight delays or disruptions. Elites are thrown to the back of the bus twice - one for the disruption and then again by loosing your upgrade becuase the search for a replacement flight is based on calss paid. Why not change the search to be by 'flown' so the search would offer flights to keep your upgrade and also coach availability?