12Witnesses and documents: notice
(1)A requirement under section 11 may only be imposed on a person by the Commissioner giving the person in question notice in writing specifying—
(a)the time and place at which the person is to attend and the particular subjects concerning which the person is required to give evidence,
(b)the documents, or types of documents, which the person is to produce, the date by which and the person to whom they are to be produced and the particular subjects concerning which they are required.
(2)Notice under subsection (1) is to be given—
(a)in the case of an individual, by sending it in accordance with subsection (3) addressed to the person at the person’s usual or last known address or, where the person has given an address for service of the notice, at that address, or
(b)in any other case, by so sending it addressed to the person at the person’s registered or principal office,
but may only be given if the address in question is in Wales or in England.
(3)A notice is sent in accordance with this subsection if it is sent—
(a)by a registered post service (within the meaning of the Postal Services Act 2000 (c. 26)), or
(b)by postal service which provides for its delivery by post to be recorded.