Pardon my retardedness, but what fare class buckets should I be looking at (on seatcounter.com, thanks MACH81) for upgrade availability? I'm guessing (only) C and/or F? Oh, wait, there's no "F" listed when you look up KLM flights. ...? I'm sooooo confused ...
(I'm seeing 3 in C on my MSP-AMS outbound leg on NWA, and 8 in C on my AMS-YVR return leg on KLM. Does that mean I should give up on trying for an upgrade on the outbound leg - see above - or does it only matter that the number be non-zero?)
Edit: I just saw this on the next-to-last page in the thread:
"On KLM-coded flights, B inventory upgrades into the D bucket.
On NW-coded flights, B inventory upgrades into the U bucket."
Now I'm really confused! People are talking about getting upgraded and being given "C boarding passes", now I see this old post saying D bucket and U bucket. And when I choose a NWA set of flights on seatcompare.com, it doesn't show me any such "U" class!
Can someone straighten this out for me?