My guess is It will be K Tv :hd ...
As they are pretty sure that it is easy to get regional market rather than ROI Market...
For Eg: If they are having only one space left to add HD channel....
They prefer to add any regional than ROI channel. As they need to add (AP, TLC, NGC Wild, NGC People Travel Xp) hd versions to get No. 1 in Infotainment but they are only need to Add K Tv;hd (Incase Tamil Market), E Tv :hd (Incase Telugu Market), Zee Bangla :hd * (Incase Bangla) or Zee Marathi :hd * (Incase Marathi market)....
By adding Single :hd They can get that whole regional market instead of adding other :hd channels...
As of Current situation if they add E Tv:hd and K Tv :hd they can easily come in par with tata sky easily in Tamil and Telugu Markets
* - Channels not launched or planned yet just for reference I used