When payment of assessments have been discontinued under the provisions of Section 25-4-57, and all obligations of the secretary for interest on advances have been met, all remaining moneys in the Special Interest Payment Fund shall remain in this fund until such time as the balance in the Unemployment Trust Fund equals at least 26 times the average weekly payment made from the Unemployment Trust Fund during the immediately preceding fiscal year as defined in Section 25-4-4(b). Thereafter the secretary may on the immediately succeeding April 1 transfer any balances to the trust fund but in no event shall unexpended assessments remain in the special fund when the trust fund equals or exceeds 50 percent of the minimum normal amount on the preceding October 1, and may thereafter be expended only in such manner and for such purposes as other moneys in the fund may be expended.