Sch 9ZA para 40
(1) A person who becomes liable to be registered under this Part of this Schedule must notify the Commissioners of the liability— (a) in the case of a liability under sub-paragraph (1) of paragraph 38, within 30 days of the end of the month when the person becomes so liable, and (b) in the case of a liability under sub-paragraph (2) of that paragraph, before the end of the period by reference to which the liability arises. (2) The Commissioners must register any such person (whether or not the person notifies them) with effect from the relevant time or from such earlier time as may be agreed between the Commissioners and the person. (3) In this paragraph “the relevant time“— (a) in a case falling within sub-paragraph (1)(a), means the end of the month following the month at the end of which the liability arose, and (b) in a case falling within sub-paragraph (1)(b), means the beginning of the period by reference to which the liability arose.