Paragraph 16
(1)
Where the person has not attained the age of 60 when he ceases to be in pensionable employment, the additional contributions consist of a lump sum which is the actuarial equivalent of the actual or prospective increase in benefits attributable to his becoming entitled to count the past period as reckonable service under regulation D3.
(2)
In any other case, the additional contributions consist of a lump sum calculated in accordance with paragraph 9(1) but with the substitution as B of his average salary.
(3)
A lump sum payable under this paragraph may be set off against any retirement lump sum to which the person is entitled.