Thanks for your message. I have submitted 2 different feedback forms but no luck, got the same response. What they say is 'We would like to inform you that award ticket changes, which is done free of charge within the scope of flight disruptions, could be carried out on alternative flights within the same cabin, the same route and the same mileage level (amount) availability.'

When I open my flight on TK mobile app, the app tells me there is a flight disruption and offers refund or change options, and the change section marks all the flights as 'FULL' if there is no X promo award availability.

If I bought the ticket with cash, I'd be given free change option as long as it is in the same cabin within -7 and +30 days (even if the ticket price for the new flight at that moment is 10x more expensive), but as I bought the ticket with miles I also need to satisfy additional condition of 'finding a flight with same mile level'. such moron move by TK.