Hi all. Flying on my first BA flight tomorrow from BOS to LIN (layover in LHR) in Club World. Just did my online check-in and have a discrepancy in my seat - wondering if this is common or something else.

In the Manage My Booking section, my seat is confirmed as 63K however when I did the online check-in, it gave me 18A with no seats available in the Upper Deck. Called BA and they have confirmed my seat being 63K and gave no reason why the online check-in gave me 18A.

Should I be worried that the online check-in gave me 18A even though BA customer service said I am confirmed in 63K? Check-in at the airport to see and complain if I don't get 63K?