3.—(1) Paragraph 1(1) of Schedule 1 to European Union (Withdrawal) Act 2018 does not apply in relation to a challenge to retained EU law where—
(a)the challenge is on the basis that, immediately before exit day, an EU instrument was invalid on any of the grounds set out in the second paragraph of Article 263 TFEU as it has effect immediately before exit day; and
(b)the challenge relates to proceedings begun, but not finally decided, in a court or tribunal in the United Kingdom before exit day.
(2) A challenge falls with paragraph (1) whether or not, before exit day, the court or tribunal has made a preliminary reference to the European Court under Article 267 TFEU in relation to that challenge.