Regarding clarification in dispute of land, Builder and flat buyer?

I am planning to buy a flat in Pune having two civil Suits on the project. Case 1 (2015):Specific Relief Act 34,38 & Indian Succession Act 6 (Reg.Civil Suit) Case 2(2016):Specific Relief Act 31,38 & Indian Succession Act 6 (Spl.Civ.Suit) My flat is ready to move in and in third (Final) phase of project. Phase 1 & 2 were started in 2011-12 and completed/sold before RERA till 2016,People are already living here.3rd phase is registered under RERA and Occupation Certificate is expected to receive in next week for phase 3. Builder has not done conveyance deed in the name of society as he is saying he will do after phase 3 completion. Phase 1 and 2 have 400 flats and Phase 3 have 60 flats. queries: 1) If court orders against of current title right of builder and declare the construction/ownership of land illegal,will flats also become illegal and flat owners needs to vacate(loss ownership). 2) Can builder do conveyance deed in the the name of society and if not how it can impact flat buyer