(1) No reinsurance agreement or amendment to any agreement may be used to reduce any liability or to establish any asset in any financial statement filed with the commissioner, unless the agreement, amendment, or a binding letter of intent has been executed by both parties no later than the "as of date" of the financial statement.

(2) In the case of a letter of intent, a reinsurance agreement or an amendment to a reinsurance agreement must be executed within a reasonable period of time, not exceeding ninety days from the execution date of the letter of intent, in order for credit to be granted for the reinsurance ceded.

(3) The reinsurance agreement shall contain provisions which provide that:

(a) The agreement shall constitute the entire agreement between the parties with respect to the business being reinsured thereunder and that there are no understandings between the parties other than as expressed in the agreement; and

(b) Any change or modification to the agreement shall be null and void unless made by amendment to the agreement and signed by the parties.