I'm sceptcal they would serve big metro cities (BOM, DEL, BKK etc). These already see a lot of competition.

With just four aircraft, I can see them using them to less competitive, more lucrative cities, particularly the Central Asian cities that TK pretty much monopolise (ALA, FRU etc). Such destinations can get away without a daily service. It would also complement the network they already have in TBS, EVN, GYD...

On GUVs, I doubt they would apply to longhaul J, unless they restricted their use to the most expensive Y fares.