Thank you. I am sorry, I did not see your last reply until now for some reason!
Then technically, this letter can be binding unto the employer. As such, if they are switching their pay periods (this itself is not such a big deal), but if doing so causes a loss of money, then this is actionable. The problem herein however is that if one speaks to the employer about this and objects, the employer can react negatively with termination, employment sanction, demotion, etc. Technically, this would be unlawful - an employee cannot have a negative action against them for enforcing their pay. This would be unlawful termination based on public policy doctrine.
The problem is whether or not the employee wishes to open up this can of worms. They can stay silent, or go to the employer and ask nicely, or, go to the employer and demand. If the employer reacts badly and sanctions the employee, the employee can sue as explained above, but whether or not they want to do this is up to them.
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