Originally Posted by
Shareholder
For international flights processed at the gate for an E or SE, they assume you are in the MLL and often will page you there to exchange boarding passes and attach the upgrade cert a few minutes before calling the flight for boarding. Domestic and Transbordere are done at the gate and if you are not there when they call names, but they knwo you've checked in, you will be caught as you board when your boarding pass is scanned. Sometimes it may be done when you're on board and already in your seat.
Earlier this year, I was cert up'd after I had plunked myself down in econ. The guy sitting next to me was puzzled when I quickly grabbed all my bags and headed to the front.
As for Op-up, I've experienced upgraded at the gate when my bp was scanned and other times, been paged at the desk. Always an exciting time when they start paging all sorts of people prior to boarding (my gf was shakng her head when I did the "please upgrade me dance" until it worked on our HKG-YYZ flight last year)
