The Board or the hearing officer, as the case
may be, shall render a written decision or, when no decision is called
for, make written findings on the application within 45 days after
the last hearing before the Board or hearing officer, subject to the
additional requirements of the Planning Code. Where the Board has
power to render a decision and the Board or the hearing officer, as
the case may be, fails to render the same within the period required
by the Planning Code, the decision shall be deemed to have been rendered
in favor of the applicant unless the applicant has agreed, in writing,
to an extension of time.