Sch 15 para 103
(1) The “ purchaser's reference accounting period ” means— (a) an accounting period of the purchaser that begins with the same date as, and ends with the same date as, the seller's reference accounting period, or (b) if no accounting period of the purchaser falls within paragraph (a), the earliest accounting period of the purchaser that overlaps with the seller's reference accounting period. (2) See paragraph 106 for provision about accounting periods before the purchaser comes within the charge to corporation tax.