Originally Posted by
Tyrolean
Cash Upgrades can book into all Business booking classes. I had Upgrades in P,Z,D,C and even J. In the old times you has to wait a bit untill P and Z were sold out to get more status miles in Z. You can guess out form price which booking class will be used.
Bid for Upgrade always book into P.
For me it booked into P although Z was for sale, it was not a bid, it was straight cash upgrade. Strange.