30. For the purposes of this division, section 87 of the Act shall be applied in such a way that the optional ancillary contributions not yet converted into optional ancillary benefits are deemed to have been converted on the day preceding the death of the member. This presumption shall, moreover, have the effect of resulting in the greatest increase in the member’s pension based on the options available under the plan. Furthermore, the pension payable to the member’s spouse shall be determined by supposing that the member was, before his death, receiving the pension resulting from the said conversion.