A friend of mine who had Rcom cdma Postpaid with UL download got it converted to 4G with UL download on 4G for Rs. 700 pm I guess.. He is living like king I am jealous of him.
Btw, for OP what after 3 months, I don't want again stupid 10G data for Rs. 999 !
For your info .. rcom still doesn't started providing 4g service.. just there network is live in some places..
and u will only get 10gb 4g free while moving to gsm.. and all data plans will be like rcom cdma till they officially starts selling new rcom gsm sims where they had only cdma license.. u can see that all cdma no transfered to gsm are latching on aircel network.. till now airtel,vodafone,idea had only launched 4g officially