If you are a nonresident on active duty and stationed in Mississippi, or a nonresident serving in the Mississippi National Guard, you count as a resident for tuition purposes at Mississippi state-supported colleges and universities. You lose the rate if you are reassigned outside Mississippi or leave the Mississippi National Guard.
Contact the admissions office at the Mississippi state-supported school you plan to attend and ask them to classify you as a resident for tuition purposes.
Your orders assigning you to a duty station in Mississippi, or proof of your Mississippi National Guard membership, and your military ID.