(1) A document may be filed by —
(a) delivering it;
(b) posting it; or
(c) transmitting it by an electronic means of communication as authorized by the Chief Justice in a practice direction;
to the court office where the claim is proceeding or intended to proceed.
(2) A document is filed on the day when it is received at the court office or, if it is received at a time when the court office is closed, on the next day on which the court office is open.
(3) If a fee is to be paid, a document is not to be treated as filed until —
(a) the fee is paid; or
(b) an undertaking to pay the fee acceptable to the registrar is received.