You should be entitled for OT for working on holidays. Let's consult Labour Dept for their advice.

EA Sec 60D

(3)(a) Notwithstanding subsections (1), (1A) and (1B), any employee may be required by his employer to work on any paid holiday to which he is entitled under the said subsections and in such event he shall, in addition to the holiday pay he is entitled to for that day --

• (i) in the case of an employee employed on a monthly, weekly, daily, hourly, or other similar rate of pay, be paid two days' wages at the ordinary rate of pay;

thank you.

is this apply to shift working hours and any salary apply for above clause [EA Sec 60(3)]?

Yes, it applies to shift work, and you are under its coverage if your salary does not exceed RM1,500 per month.