A preliminary plat shall be considered to have been abandoned by the subdivider if a final plat for such subdivision has not been submitted within eighteen (18) months from the date the preliminary plat submittal was accepted for consideration. The subdivider may be granted an extension of this time by the planning commission not to exceed six (6) months upon written application filed before the expiration of the eighteen- (18-) month period, for reasons deemed adequate by the planning commission. Any plat not submitted for final approval within the period of time set forth in this section shall be null and void, and the subdivider shall submit a new preliminary plat if the subdivision is to receive planning commission consideration. [Ord. 01-05 § 7.]