An application that is not denied or approved by the deputy director within sixty days after the application is filed with the deputy director is deemed to be approved by the deputy director as of the first day after the period. The deputy director and the applicant may extend the sixty-day period by agreement. If the deputy director gives notice of a hearing, the sixty-day period is extended to the date fixed by order of the deputy director. For the purposes of this section, an application is not deemed filed until all amendments, supplements and additional information required by the deputy director have been received.