law: 7. Period of service.-
  (1) Every member of the Regular Air Force Reserve shall be liable to serve in the Reserve-
  (a) if he is transferred to the Reserve under sub-section (1) of section 5, for the period of his Reserve liability; and
  (b) if he is appointed to the Reserve under sub-section (2) of section 5, for the remainder of the period for which he was liable to serve in the Air Defence Reserve or the Auxiliary Air Force, as the case may be: Provided that the competent authority may require any such member to serve in the Reserve for such further period or periods not exceeding in the aggregate five years as it may think fit.
  Explanation I.-For the purposes of this sub-section, "period of Reserve liability" in relation to any member of the Regular Air Force Reserve means the period for which under the terms and conditions of his service in the Air Force he was liable to serve in any Air Force Reserve if and when constituted.
  Explanation II.-In computing the period of Reserve liability in relation to any member of the Regular Air Force Reserve whose commission or engagement in the Air Force was terminated before the commencement of this Act, the period which has elapsed between such termination and the date of such commencement shall be included.
  (2) Notwithstanding anything contained in sub-section (1), no person shall be liable to serve in the Reserve after attaining the prescribed age.