O.C.G.A. § 38-2-29

For all purposes under this chapter, members of the organized militia who enter the active military service of the United States in time of war or under a call, order, or draft by the President or who enter and serve on active duty in the military service of the United States in time of peace and who thereafter return to the military service of the state shall be entitled to credit for time so served as if such service had been rendered to the state.