1) the Govt framed the Development Control Regulations for Mumbai. Under these Regulations, the Rule no. 33(7) was formed for redevelopment of cessed buildings in the Island City of Mumbai and the provisions of the policy of 1984 were incorporated in it.
the Govt. in the year 1999 amended the Development Control Regulation 33(7). The brief highlights of the amended Development Control Regulation 33(7) are as follows:
In case of redevelopment of 'A' category cessed buildings (constructed before 1940) undertaken by the landlord or Cooperative Housing societies of landlord or occupiers, the total FSI shall be 2.5 of the gross plot area, or the FSI required for rehabilitation of existing occupiers plus 50% incentive FSI, whichever is higher. Under the new policy the developer is assured of at least 50% FSI for free sale. Also the policy enables rehabilitation of all occupants on the same plot, reducing social dislocation.
Self contained flats of minimum 225 sq.ft. and maximum 753 sq.ft. carpet area are given to the old residential tenants/occupants. Shopkeepers are given an area equivalent to their old area.
2) the letter of possession must be mentioning period during which said flat cannot be sold . in addition triparte agreement executed between developer proposed society and you must be containing provisions for sale of property .
3) you can make inquires with the developer regarding sale of flat allottted to you . it is better you wait for society to be formed and share certificate issued to you by society
4) you would need NOC of society for sale of flat . also have to give inspection of agreement entered into by you with builder and society , copy of plans sanctioned by BMC etc