Moderator, Air Canada; FlyerTalk Evangelist
Join Date: Feb 2015
Location: YYC
Programs: AC SE MM, FB Plat, WS Plat, BA Silver, DL GM, Marriott Plat, Hilton Gold, Accor Silver
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In normal circumstances, you can do this ("upfare" the ticket).
But if this was part of a group purchase, it may be more difficult. Do you have access to the detailed fare rules for your booking? And it was it booked direct with AC or through a TA of some sort?