Originally Posted by
findark
Yes. Also note that if you are buying your own ticket, you can try a flight, see what the buyup offer at booking is, and cancel it if you don't like it. If you are purchasing 30+ days in advance, just buying the $659-ish P fare is probably a lot less hassle though.
Also, P fare will earn extra PQD and buy up won’t. P fare also earns 200% PQM. Buy up might get the PQM bonus, depending on where it books. (But don’t count on it)
Findark, I’m hoping you’re right about ZN being the key fare class. Lots of ZN>0 but P0 flights when I look at availability. I won’t buy a Z fare, never mind D, but will happily take a K->ZN buy up for $309 on PS flight every time.