9.—(1) If a casual vacancy arises, it shall be filled as soon as practicable in accordance with the method of filling casual vacancies decided in accordance with rule 4(4)(b).
(2) If, but for rule 6(3), a member would have served for a longer term, a casual vacancy arises when that member’s term of office ends.
(3) A member appointed to fill a casual vacancy described in paragraph (2) shall serve for the remaining part of the period for which the member he is replacing would, but for rule 6(3), have served.
(4) A member appointed to fill a casual vacancy, other than one described in paragraph (2), shall serve for the remaining part of the period for which the member he is replacing was appointed.
(5) Any period served by virtue of paragraphs (3) and (4) shall not count towards the period of nine years' service referred to in rule 6.