The disposal surplus or any balance which remains after carrying out such (if any) arrangements as have been made under paragraphs (a) or (b) of Rule 10.2 shall be retained in the CAA Section and the contributions of the Employers to the CAA Section may, subject always to the relevant provisions of Part I of the Pensions Act 1995, be reduced to the extent certified by the Actuary to be required to dispose of such surplus, or the said balance or such part of it as the Sponsoring Section Employer may decide by annual sums over a period not exceeding forty years from the date of valuation.