Every such proposed amendment initiated by motion of the Town Board or by petition of a property owner shall be referred by the Town Board to the Town Planning Board for a report and recommendation thereon before a public hearing is scheduled by the Town Board. The Planning Board shall submit its report and recommendation to the Town Board not more than 30 days after the first meeting of the Planning Board held subsequent to such referral unless, before the expiration of such thirty-day period, such proposal is withdrawn or amended or the Planning Board determines that, by reason of the complexity of the questions presented, an additional period of time, not exceeding 30 days, is reasonably required for the proper consideration thereof. If the Planning Board shall not have submitted its report and recommendation within such 30 days after its meeting or such requested additional period of not more than 30 days, the Town Board, in its discretion, may proceed to final consideration of the proposal without such report.