Can we alter our seats on a Turkish Airlines long-haul aircraft in advance?

Free seats can be altered between the time of ticketing and the end of the online check-in period. Purchased seats can be exchanged at no cost for the same seat type. For example, if you buy a basic seat, you can exchange it for another available standard seat at no extra cost. changes can be made to the seat tab in the passenger block on the booking management page until the "online check-in process" begins.

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