Does anyone know why UA does not sell Polaris First when they fly 3-class 763s on this route? It seems like they are missing a chance to monetize these seats while they are still around. Always shows F0 from the onset, and then they get filled only by non-revs and people who bother (and don't appear to even try) to apply an upgrade. UA940 is empty in F, and on my flight back on the same bird, I think I will end up as the only person in that class (unless they put all the non-revs there instead of in empty J seats - not sure if they automatically default to highest available class). They also don't upgrade anyone early except at the gate - which is really irritating as well, particularly given that 1K is going to be the best seat available.

Maybe there aren't people willing to pay for it, but it seems like a poor choice to not try and make some incremental $$.

ETA: It also only allowed me to enjoy the GF lounge for 10 minutes...if I had been here the whole pre-flight time due to being upgraded earlier, I would've eaten a full meal instead of the buffet food in the regular UC. Small worries to complain about (I like the hot food in LHR's UC), but I don't get to really enjoy the experience for much time.