Work is generally at will. They can tell you that they need you to work 55 hours a week, they can tell you what they will pay you to do so. You can accept or refuse, that’s how it is in most states.
However, in many states (and check with your state), you can quite for cause and still get unemployment benefits. For example in Minnesota, from the Department of Employment and Economic Development,
“Minnesoat Statutes, Section 268.095, Subdivision 1, provides that an applicatn who quit employment is ineligible for all unemployment benefits except when the applicant quit the employment because of a good reason caused by the employer. Subdivision 3, provides that a good reason caused by the employer for quitting is a reason that is directly related to the employment and for which the employer is responsible; that is adverse to the woker; and that would compel an average, reasonable worker to quit and become unemployed rather than remaining in the employment.”
Now, as I see it, they have eliminated your hourly position. If your state has anything like this, it should be a slam dunk. And consider this, they obviously need you, if not you would have been on the layoff list. You have leverage. If I were you, I’d ensure that your state has a similar quit for cause statute (though I honestly don’t think you’ll have to quit), and I would say to my employer that I wished to remain employed at an hourly rate of pay, I do not wish to become self employed, and if I am to become self employed, then you will need to double my hourly rate of pay and pay me for every hour I work, as that is my contract rate. At that point, they could terminate you, but then you’d have been terminated through no performance related issue.
Basically, tell them that you consider their request to be notification that your hourly position has been eliminated, and that if they would like to hire you as an independent contractor, you can negotiate the terms with them, however because you will have to pay for all your own benefits, taxes (FICA will double), etc., you are not willing to do the same job for less pay.
They are trying to take advantage of you not knowing your rights. They CAN do whatever they want, but you DON’T have to accept it.