Basically you cant use it as an ETOPS or enroute alternate. Its only open for 6.5 hrs a day .0100-0730z, and if what I was told is correct you can only use it in the morning before the wind picks up. Plus you need special approval to land there from the DGCA, unless of course its a dire emergency.
And its a one way strip for for landing (LDA 1643m avail at the moment only) and the other for take off, and there are so many equipment failures from ATC there you will always need an alternate for that airport anyway (check out the notams!)
Pilot information for Vir Savarkar International Airport @ OurAirports