The attorney or other parties may advance to a domestic reciprocal insurer upon reasonable terms such funds as it may require from time to time in its operations. Sums so advanced shall not be treated as a liability of the insurer, and, except upon liquidation of the insurer, shall not be withdrawn or repaid except out of the insurer’s realized earned surplus in excess of its minimum required surplus. No such withdrawal or repayment shall be made without the advance approval of the director. This section does not apply to bank loans, or to other loans made upon security.