(A) In all cases where an ordinance requires an act to be done in a reasonable time or requires reasonable notice to be given,
REASONABLE TIME OR NOTICE shall be deemed to mean the time which is necessary for a prompt performance of that act or the giving of that notice.
(B) (1) (a) The time within which an act is to be done, as herein provided, shall be computed by excluding the first day and including the last.
(b) If the last day be Sunday, it shall be excluded.
(2) Whenever a notice is required to be given or an act to be done in a certain length of time before any proceeding or step in a proceeding shall be had, the day on which the notice is given, or the act is done, shall be counted in computing the time, but the day on which the proceeding or step in a proceeding is to be had shall not be counted, except as otherwise expressly provided in this code.