Presently the layout or building plans sanctioned by the competent authorities like PMC, PCMC or PMRDA do not mention individual phases. Phases are decided by the developer himself. Therefore the developer can define the phases. Please note that the phases should be clearly defined along with all necessary infrastructure as well as amenities to be provided with that phase. Incase a developer shows amenities of the full project with the first phase, all the amenities will necessarily need to be completed as promised within the time. In this situation it will be necessary to state in the documentation that the amenities provided include the rights for future phases to also use the same amenities.
This issue needs to be taken up with the competent authorities as & when it frames the regulations in this regard. The Regulations that shall be framed by the Authority will provide clarity on this.