(1) The following days shall be excluded days for all purposes under the Act and these Regulations:
(a) all Sundays;
(b) any day specified as or proclaimed to be a public holiday;
(c) any day proclaimed to be an excluded day by notice displayed to public view at an Office.
(2) Whenever the last day fixed by the Act or by these Regulations for doing any act or thing at the Office falls on a day which is an excluded day, it shall be lawful to do the act or thing on the first day following such excluded day which is not an excluded day.