Originally Posted by
DidgeryDub
Didnt know that (obvs) but thats interesting, assumed they'd wait to see how many actually showed up... any bump ups I've had is always at check in or gate (and only ever on the LHR-JFK route).
That's certainly the most common way, the vast majority will occur just as you say. Sometimes you may even receive an email or a message in MMB telling you you have been upgraded.