“benefits of severance” means the member’s severance lump sum, by virtue of the Schedule Part II paragraphs 1-4, in addition to his gross pension entitlement before commutation, payable between the date of leaving and compulsory retirement age or the expiry of his existing period of extension of service;

“potential earnings” means the member’s basic salary plus any standing allowances he would have earned by remaining as a member between the date of leaving until compulsory retirement age or the end of the existing extension of service.