An Ex-Spouse Participant may (subject to proviso (b) to Rule 3.3 of this Schedule) commute part of the pension to which he or she is entitled by virtue of the Pension Sharing Order for a lump sum at the date the pension is due to commerce. The lump sum shall not exceed 2.25 times the amount of annual pension which, apart from the commutation and, if applicable, the exercise of the option under Rule 30, would have been payable to the Ex-Spouse Participant at its commencement.