If the employer has changed after an M&A, what happens to the employment succession of workers dismissed prior to the merger, and in cases where the effectiveness of the dismissal was controversial?

If the employer has changed due to an M&A, only the workers who are presently working in the company are subject to employment succession. A worker, who was dismissed prior to the merger, is not included in the employment succession.
In this case therefore, if an application for relief of unfair dismissal was submitted to the Labor Relations Commission, it will likely be rejected due to lack of proper eligibility.