At any time after a person applies to a participating corporation for an amount of financial supplement, the person may by written notice to the corporation lodged at any office of the corporation tell the corporation that the person requires:
(a) a specified lesser amount of financial supplement (not being an amount that is less than the total financial supplement already paid to the person); or
(b) a specified greater amount of financial supplement (not being an amount that is greater than the maximum amount of financial supplement that the person is eligible to obtain).