If the landowner wishes to take either such alternate action he may do so at any time within which he shall be entitled to apply for final approval, or within 30 additional days if the time for applying for final approval shall have already passed at the time when the landowner was advised that the development plan was not in substantial compliance. In the event the landowner shall fail to take either of these alternate actions within said time, he shall be deemed to have abandoned the development plan. Any such public hearing shall be held pursuant to public notice within 30 days after request for the hearing is made by the landowner, and the hearing shall be conducted in the manner prescribed in this article for public hearings on applications for tentative approval. Within 30 days after the conclusion of the hearing, the approving body shall by official written communication either grant final approval to the development plan or deny final approval. The grant or denial of final approval of the development plan shall, in cases arising under this section, be in the form and contain the findings required for an application for tentative approval set forth in this article. Failure of the governing body or agency to render a decision on an application for final approval and communicate it to the applicant within the time and in the manner required by this section shall be deemed an approval of the application for final approval, as presented, unless the applicant has agreed in writing to an extension of time or change in the prescribed manner of presentation of communication of the decision, in which case failure to meet the extended time or change in manner of presentation of communication shall have like effect.
53 P.S. § 10711