An executive order must be based on law. The Interpretation Act states very clearly that "government order means an order made by or by command of the President or by any other person under powers conferred by an Act of the National Assembly or any legislative authority." Cabinet is not a legislative authority.
In short, a law must empower the President and Cabinet to give orders. What is surprising is that no law was mentioned as the basis for changing the working hours. Secondly, even where a law empowers the President or Cabinet to issue a declaration, that order or proclamation cannot have the force of law unless it is published in the Gazette as subsidiary legislation.
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