S.C. Code Ann. § 25-1-1110

Whenever an officer is selected for promotion by a selection board convened under the provisions of federal law, he may be tendered the first available vacancy in the South Carolina Air National Guard for which he is qualified regardless of the seniority of other officers of the same grade. If he is not assigned to a suitable position vacancy in which he can be promoted, he will be discharged and transferred to the Air Force Reserve under appropriate regulations.