The Adjutant General shall be qualified for commission and shall be commissioned, if authorized by the laws of the United States now or hereafter enacted, in the Adjutant General's corps, or such other corps or branch of the service as will enable him to perform all duties required of him within the state by the National Defense Act, a federal draft, selective service or similar act operative in a national emergency. He shall have a military status in this state, if provided by the laws of the United States now or hereafter enacted, during periods in which the National Guard of Alabama is in the federal service under a call, draft, order, or other means of induction into the federal military or naval service, that will enable him to work in an advisory capacity, or other authorized capacity, to the Governor in the execution of a federal selective service or similar law, or such other office as may be authorized by the federal government, and in the performance of such duties, he shall be entitled to all allowances and to reimbursement for all expenses incident to the performance of his duties as may be provided in the military laws of this state; provided, that he shall not receive a state salary while in the active service of the United States and receiving a federal salary for such service. He shall, if called, drafted, or ordered into the federal service, on discharge therefrom revert to his state military status and such federal military status as may now or hereafter be provided by the military laws of the United States governing the National Guard on the day following his discharge from the active military service of the United States. Whenever the Adjutant General is called, ordered or drafted into the service of the United States for any reason, or the Office of Adjutant General becomes vacant for or because of any reason, while all or a substantial portion of the National Guard is in federal service, the Governor may appoint an Adjutant General to serve at the pleasure of the Governor, with the consent of the Senate. Such appointee may be selected and appointed without regard to the eligibility qualifications and requirements set forth in this chapter, but he shall have held a commissioned or noncommissioned grade in the National Guard or the Army of the United States or the United States Navy, or such appointee may be a civilian without previous military status. Such appointee shall be commissioned in the State Militia with such rank as the Governor may deem advisable. Upon the return of the National Guard or a substantial portion thereof to state control such appointee may be commissioned by the Governor as an officer of the state staff, in the Adjutant General's corps, in the National Guard of Alabama, and he may have such rank as is now or may hereafter be provided for an officer of the state staff, Adjutant General's corps, under, in compliance with and according to the provisions of the National Defense Act or acts now or hereafter enacted and Department of Defense regulations promulgated thereunder.