Following the hearings, the Planning Commission shall make a report of its findings and recommendations with respect to the proposed amendment, and shall file with the Board of Supervisors an attested copy of such report within 90 days after the notice of the first of said hearings; provided, that such time limit may be extended upon the mutual agreement of the parties having an interest in the proceedings. Failure of the Planning Commission to so report within 90 days without the aforesaid agreement shall be deemed to be approval of the proposed amendment by the Planning Commission. (Ord. 409, eff. 7/5/73; Prior code § 86218C)