The retroactive change in your hire date is only an issue if you can be considered under an exception to the At-Will Doctrine. As an employee without a written employment contract
, you fall under the At-Will Doctrine. The At-Will Doctrine means essentially, amongst other things, that the employer can change the terms of your employment, eliminate company benefits going forward, and/or terminate you without cause.
In Connecticut, an employment benefit such as vacation time, can be eliminated for At-Will employees. In Connecticut, an employer is not required to provide its employees with vacation benefits, either paid or unpaid. If an employer chooses to provide such benefits, it must comply with the terms of its established policy or employment contract. See Conn. Stat. 31-76k; Gagnon v. Housatonic Valley Tourism Dist. Comm., 888 A.2d 104, 92 Conn. App. 835 (2006); Santengelo v. Elite Beverage, Inc., 783 A.2d 500, 65 Conn. App. 618 (2001); Fulco v. The Norwich Roman Catholic Diocesan Corp., 609 A.2d 1034, 27 Conn. App. 800 (1992).
Thus, the employer is bound by the employment manual and that would mean that the employer's retroactive change of your hire date, which has the effect to breach the vacation time you have legally become entitled to pursuant to the employment manual, could be considered illegal.
department does not enforce these sort of provisions, leaving the duty to enforce this in the hands of the employee. Accordingly, you would need to file a lawsuit if the employer will not agree to correct this. The lawsuit would be for breach of employment contract.
What I suggest you do first (because filing a lawsuit may end up causing you to be fired) is to produce some proof that you worked for the company prior to the acquisition/merger. This needs to be put into a written formal complaint to submit to HR and to the company management (or the in house counsel if the company has one).
Are you the only employee this has happened to? Are there other employees who have been with the company as long as you have and who still have the correct amount of vacation time?