(4)A Member of the Appellate Tribunal shall hold office as such until he attains,—(a)in the case of the Chairperson, the age of seventy years;(b)in the case of any other Member, the age of sixty-seven years:Provided that a person who has not completed fifty years of age shall not be eligible for appointment as Member:Provided further that the Member may retain his lien with his parent cadre or Ministry or Department, as the case may be, while holding office as such for a period not exceeding one year.