20.—(1) A member—
(a)may stop paying his ARCs before the end of the ARC payment period if he notifies the Committee and his employing authority in writing that he wishes to do so; and
(b)must stop doing so if he ceases to be an active member.
(2) If a member stops paying his ARCs before the end of the ARC payment period—
(a)on leaving his employment on the grounds of ill-health and his employing authority makes a determination in respect of him under regulation 20(2) or (3) (early leavers: ill-health) of the Benefits Regulations; or
(b)on his death,
he is treated as having paid his ARCs up to the end of that period.
(3) If a member stops paying his ARCs and paragraph (2) does not apply to him, he must be credited with additional pension of an amount determined by the Government Actuary, having regard to the ARCs he paid before he stopped.