4. The Commission shall request ACER to submit to it, within a reasonable period not exceeding six months of receipt of the Commission’s request, non-binding framework guidelines setting out clear and objective principles for the development of network codes relating to the areas identified in the priority list. The request of the Commission may include conditions which the framework guidelines shall address. Those framework guidelines shall contribute to market integration, non-discrimination, effective competition, and the proper functioning of the market. Upon the reasoned request of ACER, the Commission may extend the period for submitting the framework guidelines.