and ~$250 upgrades are becoming more and more common

some examples for me >

when flying as 2 pax in Y where its 3 seats together, have bought extra seat

$1500 per eos airlines all-J after buy one get one free in 2006
amazing, access to quintessentially (dinner at mortons club london)
i dont think there were any super cheap nonstop transatlantic Y then

more than that for Y nonstop transatlantic (should've checked buying miles)

$2200 per domestic transcon F when Y was $1500 per for 2 middle seats

did a walk up booking once, should have asked how much for F upgrade