Hi and welcome to JA,
This is what I suggest:
1. An immediate lawsuit in law alleging that M breached the contract
2. Include a claim in equity claiming laches on M's part. That means that it sat on its rights concerning your alleged breach for so long that you have been damaged. You have relied on the validity of the contract in taking orders and otherwise operating your business,
3. On filing the suit, file an Order to Show Cause. This is an application to the court to be decided in a day or two ordering M to continue to operate per the contract unil the lawsuit is decided.
4. Include in the application an order that M not selectively take a different position with other companies in your position.
Since M has done business in your state and you have suffered damages in your state, you can sue M in your state under what we call "long arm" jurisdiction established by the U.S. Supreme Court in the case of International Shoe Co. v. Washington. This case recognized the reality that companies like M do business in many states and should be required to defend themselves in those states rather than force all potential plaintiffs to come to M's state to sue.
To find a lawyer in Arizona:
Go online to Martindale.com. This is a nationwide directory we lawyers use to find highly qualified legal specialists in various fields. These lawyers are NOT in Martindale because they paid to be included. They are there because they are rated as QUALIFIED by other lawyers in their field of expertise and geographic area as it applies to you and your kind of case. The process is that these other lawyers are asked to fill out questionnaires giving their opinion of the quality of the work of the law firm that ultimately appears in Martindale.
The site is organized geographically and by legal specialty. Consult with two or three and select the one you are most comfortable with.
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