Mississippi Code Title 63. Motor Vehicles and Traffic Regulations § 63-1-49

(2)(a) Any person in the Armed Services of the United States, who holds a valid license issued pursuant to this chapter and is out of state due to military service at the time the license expires, may renew the license by mail or by online renewal services while out of state due to military service or at any time within ninety (90) days after being discharged from military service or upon returning to the state without payment of any delinquent fee or examination, unless the department has reason to believe that the licensee is no longer qualified to receive a license. The person shall make proof by affidavit of the fact of the person's current military service or of the time of discharge or return. The expiration of the license of a military person under the provisions of this paragraph (a) shall not affect the validity of the license, but the license shall continue to be valid and permit the person to operate a motor vehicle in this state for a period of ninety (90) days after discharge from military service or return to the state or until renewal of the license, whichever occurs first.

(b) The provisions of paragraph (a) of this subsection (2) also apply to a dependent of a person in the Armed Services of the United States who is out of state due to military service if the dependent resides out of state with the Armed Services member and the license of the dependent expires during the family member's absence from the state. The Commissioner of Public Safety may adopt such rules and regulations under the Administrative Procedures Act as may be necessary to implement the provisions of this paragraph.