Thank you for trusting your question to JA today. I am a licensed attorney with over a decade of law practice and over 20 years of experience in the legal field. I’m happy to be of assistance.
I think you may be misinterpreting the law there.
If I work this week thinking I am making $10 an hour, my employer can't pay me $9 an hour for this week. I should have the ability to decide if I want to work for the lower rate. However, the day I get a paycheck for only $9 an hour, I am on notice from that moment forward that that is what they are willing to pay.
So, on these facts, the most your employer would have to payback would be any pay period where you worked before finding out about the lower rate. There is nothing requiring an official, specific type of notice.
In January, when your pay was cut, you could only truly sue for the pay period that you worked before becoming aware that they were cutting your pay. The fact that you are asking this question indicates that you become aware of the cut, which legally equates to sufficient notice.
Last week, when they cut your pay again, if you worked the pay period before expecting a certain rate of pay for it, and this change effected that pay period, then you'd have that as an argument for back pay too.
So, at most, you're talking about back pay for just two pay periods, if you worked that pay period expecting one rate and got paid another.
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