Hi
The holiday apparently starts on 15 November and lasts the rest of the week. We just checked with our bank, the Denizbank and they are open on Monday 15 until lunchtime and then closed the rest of the week opening again on 22 November. They said they would stock the ATM machine up but personally I wouldn't rely on the money lasting a week in it. A number of restaurants are also shutting for a week, that is in addition to those that have already closed.