4.—(1) Subject to sub-paragraph (2), there shall be no rates due and payable by an eligible person for a year earlier than that in which the agreement is entered into.
(2) Sub-paragraph (1) shall not apply in the case of rates due and payable in respect of the qualifying hereditament by an eligible person who is the surviving partner of a person who had made an agreement under these Regulations in respect of that hereditament.