Computing Hours worked on Rest days, Special Non-Working Holidays and Legal Holidays for Monthly Paid Employees

I have worked in a private company and paid as a monthly employee of Php 12120 per month, since half of a month of it was paid as Php 6060. If I work on a rest day or special non-working holiday the company would only pay me an additional 30% of my daily rates since they used 360 days as a divisor for computing my salary, meaning if my monthly pay is 12120 divided by 30 days equals my daily rate of 404. since 404 is my daily rate, 404 divided by 8 hours is equals to my hourly rate of 50.5. Hourly rate of 50.5 x 1.3 equals to 65.65. Since Php 6060 is my basic regular pay for half month. If I render work on a rest day should I be paid a separate Sunday overtime rate of 65.65 (130%) per hour? Total of
Php 6585.20 for 8 hours rest day OT including my pay for half the month.
The company had also paid same way on legal holidays. Example: If I work on a legal holiday I would only be paid an additional 404 if I don't work on that day I will also be paid the same way. They say that if I was scheduled to work on a special holiday or a legal holiday I should go to work for it cause it would be insubordination if I reject it. I need legal advice on this cause labor code has no specifics on computation. Thanks!

it is up to the management to determine what divisor to use, but once decided, they cannot just change it.

At 360, it means all except 5 days of the year are paid.

If sunday is meant to be your rest day, you should be paid rest day premium of 30%. if you are made to work on a legal holiday, you should get 100% premium and 30% on special days.

if you are required to report on a holiday, then you must comply.

Since that 5 days are not paid and 30 days is only paid in a month, are we allowed to make an absent during the months having 31 days without any deductions to our salary?

no. ask the company which specific 5 days they are excluding.

Dear Atty:
I am working in a government agency under "contract of service" and i would like to ask if legal holidays are considered as hours not worked. Their reason is that COA said that legal holidays should not be credited and must be deducted due to no work no pay rules. please enlighten me Sir. Thank you