Originally Posted by
TheSkyGuy
They can only tell if you were upgraded at the gate, as the seat map will show you as a UPG. Otherwise, no.
Not true. Ticket fare class is shown on the FA roster that lists passenger names. So when they are greeting you by name, they also see “C” for international business upgrade, “R” for domestic upgrade vs “J” for paid business, and so on.
Again, it shouldn’t matter, but they do see it.