s 392 Alteration of accounting reference date
(1) A company may by notice given to the registrar specify a new accounting reference date having effect in relation to— (a) the company's current accounting reference period and subsequent periods, or (b) the company's previous accounting reference period and subsequent periods. A company's “ previous accounting reference period ” means the one immediately preceding its current accounting reference period. (2) The notice must state whether the current or previous accounting reference period— (a) is to be shortened, so as to come to an end on the first occasion on which the new accounting reference date falls or fell after the beginning of the period, or (b) is to be extended, so as to come to an end on the second occasion on which that date falls or fell after the beginning of the period. (3) A notice extending a company's current or previous accounting reference period is not effective if given less than five years after the end of an earlier accounting reference period of the company that was extended under this section. This does not apply— (a) to a notice given by a company that is a subsidiary undertaking or parent undertaking of another UK undertaking if the new accounting reference date coincides with that of the other UK undertaking or, where that undertaking is not a company, with the last day of its financial year, or (b) where the company is in administration under Part 2 of the Insolvency Act 1986 (c. 45) or Part 3 of the Insolvency (Northern Ireland) Order 1989 (S.I. 1989/2405 (N.I. 19)), or (c) where the Secretary of State directs that it should not apply, which he may do with respect to a notice that has been given or that may be given. (4) A notice under this section may not be given in respect of a previous accounting reference period if the period for filing accounts and reports for the financial year determined by reference to that accounting reference period has already expired. (5) An accounting reference period may not be extended so as to exceed 18 months and a notice under this section is ineffective if the current or previous accounting reference period as extended in accordance with the notice would exceed that limit. This does not apply where the company is in administration under Part 2 of the Insolvency Act 1986 (c. 45) or Part 3 of the Insolvency (Northern Ireland) Order 1989 (S.I. 1989/2405 (N.I. 19)). (6) In this section “ UK undertaking ” means an undertaking established under the law of any part of the United Kingdom ....