Originally Posted by
gnaget
I was looking at availability on BCD (and another site non-public site) for SFO-CPH that is showing R class before Y, suggesting that it is in business. It was zero until around 48 hours before departure when business dropped from C9 D9 to C4 D0, but R became R3 and then R4 hours before departure. (So it shows C4 R4 Y4, etc...) This suggests to me that it shows availability for paid/ auction upgrades. What do others think?
Historically, R was a non-revenue booking class, which would never show up on any availability tools.
It sounds like a reasonable explantion, they do have to flag the inventory for paid upgrades somehow. I seem to remember that UA also used R to show space available for upgrades with GPUs, but as I never were a big United flyer and have only ever used friends' GPUs I am not the most reliable source on that.