I do have an AC Aeroplan membership. Made a little progress - When I log into AC manage my booking I see all the usual stuff about seat selection, baggage, passport info but there's nothing about FF#'s. I had to go to my main AC user profile - in there I was able to add UA MileagePlus # (see below). What I remain unsure of is whether having the UA MP# number in my main AC profile will have any effect on a specific ticket.



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