Any notice which under this Act is to be given to any person by the lead enforcement authority shall be so given—
Any such notice may,—
Any application or other document which under this Act may be made or given to the lead enforcement authority may be so made or given by sending it by post to the lead enforcement authority at such address as may be specified for the purposes of this Act by a general notice.
For the purposes of subsections (1) and (2) above and section 7 of the Interpretation Act 1978 (service of documents by post) in its application to those subsections, the proper address of any person to whom a notice is to be given shall be his last-known address, except that—
and for the purposes of this subsection the principal office of a company registered outside the United Kingdom or of an unincorporated association or partnership carrying on business outside the United Kingdom shall be their principal office within the United Kingdom.
If the person to be given any notice mentioned in subsection (1) above has specified an address within the United Kingdom other than his proper address, within the meaning of subsection (4) above, as the one at which he or someone on his behalf will accept notices under this Act, that address shall also be treated for the purposes mentioned in subsection (4) above as his proper address.