Can the Army violate my contract states that I can't be involuntarily mobilized or deployed for 24 months? Do I have any recourse?

When I wrote the Reserve Transition Contracts and they had 24 months of stabilization, it was defined as 24 months stabilization from being deployed to contingency operations, not 24 months stabilization from being mobilized.

Also, if you review the stabilization memorandum you would have signed with your contract for the Reserves (the NG ones are different and state you can be mobilized for active duty State missions) you will see that it says you may still be mobilized. Your first general officer may waive it

SSG,
Former barracks lawyer here. Jk
The 24-month deployment deferment can be overridden for extreme circumstances, but it cannot be done by just your company. It can only be revoked by the first General Officer in your Command.

I think that would be a BG (O-7), but I also have some memory from the time I was leaving active duty and had deferment offered to me that it could be a COL (O-6). Can’t remember for a fact.

Walk (not wait for it to rise to his level) your paperwork up through your chain of command to your first General Officer. He's the one that can give you an approved 30 day deferment. Take all your documents with you including a set of activation orders for his Aide/G1 to reference.
Be prepared to explain in a 5 W's format.
WHO: Your short, short BIO
WHAT: The Course of Study. Main things you have learned and qualified (Radiology/RN/Surgery Nurse, etc).
WHEN: You complete, when you test and when you will be prepared to return to active duty.
WHERE: School Name, Type National Qualifications and Degrees.
WHY: The reason you are speaking with him - to seek a temporary deferment based on what you've already told him.
I doubt you will get totally out of activation BUT it may not be back to your previous unit. You might also ask the General while you are there for Officers Candidate School (Bachelor's) OR a direct commission (if its a Master Degree).
Good Luck.