So I guess I am the idiot that didn't realize that if I closed my Aeroplan credit card, they would simply take the certificates back. Should have read the fine print - but now I realize what a sneaky thing this was compared to just receiving points. I had a flight booked with the certificates but the flight got canceled by the operating airline, and the certificates got redeposited. So it's been over a year and I wasn't sure when to use them next, but I read that they have no expiration date, so I wasn't worried. Except, they do expire if you don't keep renewing your qeroplan annual fee card, which is essentially like having to pay an annual fee to keep your points from not expiring. these certificates were already worth less than points value simply because they aren't worth as much, potentially. I closed my credit card a month ago, yesterday I finally found a ticket I wanted to book and suddenly couldn't find the certificates in my account anymore.
I guess I learned my lesson to not go for that ever again. I earned them by doing the spend, I paid my annual fee and they hold you hostage to it. Never again, Aeroplan.