So, after we were changed from 1E+1F to 1E+4D, and I was able to immediately change it back to 1E+1F via the hotline, at check-in the agent said 1F is broken and it was again reassigned. Then on the flight someone else was sitting in 1F normally lol. Also lots of other passengers split apart and trying to switch seats. What a mess Turkish is...

On another note, today I suddenly received a new booking confirmation for our return flights out of nowhere. No apparent changes, everything still confirmed, but now I'm suspicious...