The month of December is the busiest month of the year for HR. In my office the work load triples that month and that is not even close to an exaggeration; if anything it's understated. They had a great deal more to do than babysit your claim through the third party administrator so that you would get an immediate answer.
Two things I am tired of typing: 1.) A wrongful termination does not mean that you were fired for something you didn't do; it means that you were fired for a reason prohibited by law. 2.) The above answer, whatever it is, assumes that no legally binding contract or CBA expressly says otherwise. If it does, the terms of the contract apply.