13. The time limits otherwise applicable to the amendment of a company tax return do not apply to any amendment to the extent that it is made in consequence of a 2020 or 2021 loss carry-back allocation statement being submitted in accordance with these Regulations.
14.—(1) If an officer of HMRC considers that a person has received any overpaid relief, the officer may make an assessment in the amount which ought in the officer’s opinion to be recovered.
(2) The amount assessed in paragraph (1) is to be treated as an amount to which paragraph 52 of Schedule 18 to Finance Act 1998(1) (recovery of excessive repayments etc) applies.
1998 c.36. There are amendments to paragraph 52 but none is relevant.