Today I found download link on Partner Source for Microsoft Dynamics NAV 2016 IN Localization, so as agreed by Microsoft it is here in May’16. After almost 7 months from global release Microsoft launched Microsoft Dynamics NAV 2016 Indian Localization version.
So for India there is no NAV 2015 version. Now the upgrade path is from NAV 2013 R2 to NAV 2016 directly.
Please wait for What’s new available in NAV 2016 IN version.