(a) The final map shall be filed for final approval not later than twelve months after the date of approval of the preliminary plan; otherwise, it will be considered void unless an extension is requested in writing by the developer and granted by the Planning Commission, in writing. The subdivider shall submit six copies for approval.
(b) The final plan shall be considered officially filed after it is examined by the Commission and is found to contain all of the data required under Section 1117.05. The final plan shall be filed not less than fifteen working days prior to the Commission's meeting at which it is to be considered.