Have Military Law Questions? Ask a Military Lawyer.
Thank you for your question today, I look forward to assisting you. I have nearly 20 years of legal experience in various disciplines, including JAG.
The only way to do this is to request a transfer from your active duty unit to the IRR.
Switching from one to another is not a legal right. I'm not certain why you have a reserve duty commitment on the end of your service, but it apparently was part of your contract and so you are legally obligated to do it unless your reserve unit is willing to allow the transfer.
This is a command decision, not a decision by retention. Your current command can't really do it either. This is why they can only offer you reenlistment or moving you into the SR.
It is a command decision to be made by your reserve unit of assignment, so you'll have to enter, approach your chain of command and ask for this transfer and if they refuse, you'll have to serve out the time remaining in your SR requirement.