Originally Posted by Empress
Your argument is valid but in a span of few minutes that you have, it'll be hard to convince the GA if he/she already has their mind made up that the cert is used. They have a way of accessing past bookings to verify that but not something that can be done easily and they certainly won't do it when they're boarding a flight (which is when they'll see the cert).
*grumble*
It's for UA stock AC790 LAX YYZ next week

It will have to be done at the gate but I guess if I have time I could go to the MLL and ask for a concierge to help me out...
Besides, how can someone get a hold of marked certs anyway? I must've stolen it then if they think that they were truly used...