Despite what you were told, I think it may be possible that you were passed over. If the upgrade clears and you don't have stickers, you can't check in, as you know. It sounds like you did actually OLCI, and received the message sort of after-the-fact. Inasmuch as they don't seem to allow one to be checked-in, upgraded and not have stickers (and you are checked-in and don't have stickers) it is possible that this is impacting the upgrade.
Just speculation on my part based on some known facets of the program, of course.
Cheers.