Except in a case covered by section 65AA, if :
(a) the employee has retired because of permanent incapacity or permanent invalidity; and
(b) the former employee has lodged with the Commissioner:
(i) written notice of the retirement; and
(ii) a copy of a certificate signed by 2 registered medical practitioners certifying that the former employee is unlikely to be able to work again in a capacity for which he or she is reasonably qualified by education, training or experience;
the Commissioner must pay the amount of the shortfall component to the former employee.