4 Service of notices
A notice under section 2(1)(c) of the Act is duly given to the landlord or tenant (or prospective landlord or tenant) if—
(a) it is given to them by hand;
(b) it is left at their proper address;
(c) it is sent by post to that address;
(d) it is transmitted in a form of electronic communication accepted by the recipient of the notice; or
(e) it is provided by any other means accepted by the recipient of the notice.