I am waitlisting the 77W flight from IST to LHR for the early morning. However, it seems quite full. Not sure whether if I can change there last minute. I am booked tentatively with a confirmed booking of TK1981 with A321-200 (without mentioning it's a sharklet one) How likely is the chance that I will have to sit on the old business class seat. As I learnt most the A321 are equipped with regional A321 business seat, but I saw some flight reports online recently there are old seats?