Originally Posted by
wharvey
Oftentimes, the day of your flight, you can request to go on an earlier standby. I am not familiar with Air Canada specifically, but would expect they would consider a request if space is available. You may want to check out the Air Canada forum.... so great advice can be found there.
AC has a fixed fee for same-day changes so the chances that they'll do it for free are slim. However there's no harm in asking. Traditionally airlines loved this since it increases their odds of filling that empty seat. The sooner they could get you out of their hair the better.