I did a points conversion yesterday afternoon (RBC Avion to BA Avios) - even though there's a bonus coming soon, because I needed the points for a flight I want to book. And wouldn't you know it, some other Avios I thought would take a while to post came through this morning, so I don't need the extra points and want to save my Avion points for the conversion bonus.

Can I call to cancel the transfer if it's within 24 hours? I can give it a shot, but I don't want to bother with the call if anyone knows for sure it's not possible. TIA!