There is an Insufficiency Assessment Reserve Fund. The Insufficiency Assessment Reserve Fund shall be maintained by the Association and shall consist of assessment payments collected by the Association and interest, if any. Except as provided in paragraph (2) of this subsection, the Association shall hold money of the Insufficiency Assessment Reserve Fund in trust in a separate interest–bearing account in a financial institution in the State for the use of the Fund. The Association may authorize the financial institution where the money is deposited to invest all or part of the money in investments allowed for casualty insurers, as provided in §§ 5–601 through 5–609 of this article. An Association member shall deposit with the Association any gross excess surcharges received because of a future assessment not later than October 15 after the surcharge year in which the gross excess surcharge was received.