18(1)Subject to paragraph 19 below and to the provisions of this paragraph, where the terms of a policy are varied, the question whether the policy after the variation is a qualifying policy shall be determined in accordance with the rules in paragraph 17 above, with references in those rules to the new policy and the old policy construed for that purpose as references respectively to the policy after the variation and the policy before the variation, and with any other necessary modifications.
(2)In applying any of those rules by virtue of this paragraph, the question whether a policy after a variation would be a qualifying policy apart from the rule shall be determined as if any reference in paragraphs 1 to 9, 12 and 13 above to the making of an insurance, or to a policy’s term, were a reference to the taking effect of the variation or, as the case may be, to the term of the policy as from the variation.
(3)This paragraph does not apply by reason of—
(a)any variation which, whether or not of a purely formal character, does not affect the terms of a policy in any significant respect, or
(b)any variation effected before the end of the year 1968 for the sole purpose of converting into a qualifying policy any policy issued (but not one treated, by virtue of paragraph 8(1) and (2) of Schedule 14, as issued) in respect of an insurance made after 19th March 1968.