I can give three recent experiences within the last 3 months. All long-haul C trips from different places in SE Asia to IST and back (but never beyond IST). Usually all my (and my GFs) TK flights posted to BD without issues within 2-5 days from the flight. There are sometimes difficulties when the FFP number is entered as some staff in SGN for example have not heard of BD so giving them the airline code helped.

In one instance my SGN-BKK leg posted, but my BKK-IST didn't and I had to retro-claim it with BD. That was because the folks in BKK (who supposedly have control over that flight) decided to reseat me on the BKK-IST sector and by doing so somehow managed to erase my BD number when issuing the new BP. Apart from that I haven't encountered any issues.