Originally Posted by
brunos
First awards/upgrades book into the F, the discounted F revenue bucket (P is full fare). When flights fill up in premium cabins (risk of J overbooking) or a couple of seats taken in First cabin, then the F bucket is zeroed. On a 772 it is not unusual to see P2 F0.
Sorry, it's indeed F (I was months in advance ;-). And F also holds some revenue fare basis.