You would need to cancel the Advantage plan and buy directly from the AAA website if they offer the Desktop program. Some partners just have discounts for the Online version. You aren't getting any price advantage using the Advantage subscription. You just get it as soon as it comes out.
Here is a FAQ on the benefits of using the Advantage program
https://ttlc.intuit.com/questions/1901492-what-is-turbotax-advantage
You have until October 31 to cancel Turbo Tax Advantage
https://ttlc.intuit.com/questions/1901052-cancelling-or-refunding-your-turbotax-advantage-enrollment-and-order