Bro, you should still receive the 13th month pay notwithstanding the mode of wage payment. You can also find the calculation here.
HTH.
FAQs on 13TH MONTH PAY
Who are covered or entitled to the 13th month pay?
All rank-and-file employees who have worked for at least one (1) month during the calendar year, are entitled to receive 13th month pay regardless of the nature of their employment and irrespective of the methods by which their wages are paid.
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