OK, thanks for the additional information.
Your suspicions are correct, and I am glad that you found the DOL website. From what you have described it certainly sounds as though you have a claim for back wages.
I also suspect that the company received advice from their lawyer or CPA that they were violating the labor laws. This is probably why they initiated the payroll change a few months back.
The only part of the information as to classifying your position as contract would be the lack of withholding. Everything else you described is that of an employee, not contract labor.
Here's what you need to do. File a claim with the Texas Employment Commission AND the Department of Labor. Now, I would strongly recommend that you hire an attorney to assist you, and you will be able to find one. In certain circumstances attorney fees are recoverable, and there will be plenty of back pay to compensate an attorney on a contingency basis.
You probably found out that you are entitled to double the back pay owed. You can go back two years. If you averaged 30 hours of overtime each week, that is equivalent to 15 hours of straight pay owed which is then doubled, (i.e. 30 hours pay, per week). However, if you can prove that the violation was "willful", then the amount is tripled, and that is where you really need an attorney. Either way, this is a considerable amount owed.
You need to first talk with a good employment lawyer first. There is no substitute for that, and they may have a preference of where to file, what agency to file with first, etc. It would also be helpful if you can explain to the attorney that others may be similarly mistreated and willing to file.
Absolutely pursue this, and I wish you the best with it.
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