Originally Posted by
mabramovich
In any case, now you are saying that as long as a flight is not oversold, I should be able to get onto it. Is that sort of the unofficial line? One could find out if a flight were oversold by calling AC Reservations, right?
Which is what was posted already. Same day change is not available for any flight with seats for sale, it's available on any flight that is not oversold. These two situations are not the same.
You we're travelling on a busy day, and it's possible that at the time you requested the change, flights were oversold.
AC Res should have access to this information - whether they tell you or not is another story.