I just found out that a few of a friend's TK flights have not been posting properly. Upon closer inspection, it seems that flights to IST post fine. Its only the flights from IST to wherever that seem to have issues... even though your boarding passes have the correct new BD numbers on them.

A simple solution may be to ask the TK transit desk at IST to reprint your boarding pass and to give them your BD # there again. Make up some excuse to say you want your seat changed or something.

It *May* work... don't know. I'll find out next week when I fly via IST to BKK and see if they're do that at the transit desk.