27.—(1) Paragraph (2) applies where—
(a)a requirement to register applies to a group or undertaking under article 24 or 26; and
(b)a change described in section 1 of Part 3 of Schedule 6 applies to that group or undertaking after the qualification day but before the group or undertaking makes an application for registration within the time provided under article 12 (“the post-qualification period”).
(2) Where this paragraph applies—
(a)a group or undertaking to which article 24 or 26 would otherwise apply must instead register as a participant as provided by section 1 of Part 3 of Schedule 6; and
(b)other undertakings affected by such change must comply with that section.