if you mean that any data left over from your 200 gb is carried forward to next month , then no , 200 gb validity is 30 days only,been using it since 2011 since the only alternative to me is mtnl wired line but this works out better then any plans they have i get a stable 1mbps in morning which goes to 2mbps after 6 pm and from 10 to 11 pm it is non stop 3.5 the max in delhi i can get .
of coerce it has is problems some times you can hardly browse in mornings , sometimes it disconnects every 2 mins or so most of times things work out in couple of hours . then only time i had to call CC was in Nov when they some how managed to cap my speeds to 50 kb , speaking to them or any one for that matter din't help, it worked out on in it's own albeit after nearly 40 days !!!!