In any proceedings for an offence under this Act it is a defence for the person charged to prove—
(a) that his act or omission was due to a mistake, or to reliance on information supplied to him, or to an act or omission by another person, or to an accident or some other cause beyond his control, and
(b) that he took all reasonable precautions and exercised all due diligence to avoid such an act or omission by himself or any person under his control.
If in any case the defence provided by subsection (1) involves the allegation that the act or omission was due to an act or omission by another person or to reliance on information supplied by another person, the person charged shall not, without leave of the court, be entitled to rely on that defence unless, within a period ending seven clear days before the hearing, he has served on the prosecutor a notice giving such information identifying or assisting in the identification of that other person as was then in his possession.