12.—(1) Subject to paragraph (2), the Registrar General may send by post a household pack to such households in the address register as the Registrar General considers necessary for the purpose of the census in advance of census day, or as soon as possible thereafter.
(2) The Registrar General may choose not to send a household pack by post, but instead to prepare for the relevant census officer to arrange delivery of that pack in accordance with regulation 13.
(3) The Registrar General may send by post an individual pack to any elector at an address in the address register.
(4) In respect of each pack sent in accordance with paragraph (1) or (3), the Registrar General must ensure that a record is made in the questionnaire tracking system in accordance with Regulation 8(1).