Non-diminution of benefits

Does this fall under Non-diminution of Benefits Rule (Labor Code).
The principle of non-diminution of benefits states that: “any benefit and supplement being enjoyed by employees cannot be reduced, diminished, discontinued or eliminated by the employer.”

In our company, we are entitled to 5 VL and 12 SL which we can use any month of the year without any conditions. In short, we can use 2 VL in January without any problem. But this year, they oriented us about certain "changes". First, we are now given 6 VL and 12 SL BUT we can only use 1 VL every 2 months and 1 SL every month. So let's say I filed for 4 VL in January, but I'am only entitled to 1 VL, what the company would do is that they will only pay in full 1 VL the rest (3 days) will be paid in half. In short, we do not get paid in full unless we have earned it. Same goes with our SL. If unfortunately you get sick and filed for 5 days SL in March, you will only get paid for 3 days the rest (2 days) half na. Ang katwiran ng HR namin is that hindi naman nila "binawasan" yung benefits pinalitan lang ang pagbigay at paggamit daw. Pero I don't know, parang hindi naman beneficial sa employees yan eh. Actually, reduced nga in my opinion. Can they implement this without our approval?

Thanks sa mga sasagot.

This is not a non-diminution of benefits case as your benefits are still the same, mas lalaki pa nga because you will be paid half in case of the excess. The only thing is that the application of leaves is unreasonable. The VL could be upheld for management purposes but I believe the SL, not kasi regardless of any knowldge of law, alam mong unfair yan kasi a person of his right mind knows that he will never know when he will get sick and for how long.

Kung may collective bargaining agreement kayo, di nila pwede i-implement without your approval so long as your CBA provides so.