What is there to argue, the boss has to run his business. You just follow his instructions. The following is the law about working hours:
60A. Hours of work.
(1) Except as hereinafter provided, an employee shall not be required under his contract of service to work:
(a) more than five consecutive hours without a period of leisure of not less than thirty minutes duration;
(b) more than eight hours in one day;
(c ) in excess of a spread over period of ten hours in one day;
(d) more than forty-eight hours in one week: