Guys, I was thinking of changing the Idea sim to new V! one, to get VoLte (though I will lose the higher speed limit). But suddenly by yesterday evening, VoLte started working in my old Idea sim. I was very happy. But today morning, I saw the news about tariff hikes 25% by Airtel.
Looks like Airtel is waiting for VoId's VoLte recovery to hike the tariffs, else too many people from VoId (if without VoLte) will come to their network and congest them.. Anyway, now I am happy for the VoLte in VoId. I just need to check the same in roaming circles in coming weeks..