Legal Question in Employment Law in California

I don't think so. The vacation pay that was earned, at the old rate, should in fact be paid at the old rate. Any vacation pay earned or to be earned going forward, after the rate change, would be at the new rate. So let's say you were to quit, and at the time you leave, you have earned 87 hours at the old rate, pretend 10 hours at the new rate. They should pay you 87 X 11.75 + 10 X 11.16. If they fail to pay you what is the proper ( say all 97 hours at the new rate of 11.16) within 72 hours after you leave, you could be entitled to waiting time penalties under labor code section 203 of up to an additional 30 days pay, plus interest, for the employer not paying you all that is correctly owed in a timely fashion. You could bring such a claim to your local labor board. If you look up "DLSE" under google, you can get a list of the different labor board offices in CA. good luck.