Proceedings for an offence under subsection (1) above (but not proceedings of a kind falling within subsection (4) above) in relation to a mechanically propelled vehicle— shall not be commenced after the end of the period of three years beginning with the day on which the offence was committed; but subject to that, may be commenced at any time within the period of six months beginning with the relevant day. In subsection (4A)(b) above “ in the case of a prosecution for an offence under subsection (1) above by a public prosecutor, the day on which sufficient evidence to justify the proceedings came to the knowledge of any person responsible for deciding whether to commence any such prosecution; in the case of a prosecution for an offence under subsection (1) above which is commenced by a person other than a public prosecutor after the discontinuance of a prosecution falling within paragraph (a) above which relates to the same facts, the day on which sufficient evidence to justify the proceedings came to the knowledge of the person who has decided to commence the prosecution or (if later) the discontinuance of the other prosecution; in the case of any other prosecution for an offence under subsection (1) above, the day on which sufficient evidence to justify the proceedings came to the knowledge of the person who has decided to commence the prosecution. For the purposes of subsection (4A)(b) above a certificate of a person responsible for deciding whether to commence a prosecution of a kind mentioned in subsection (4B)(a) above as to the date on which such evidence as is mentioned in the certificate came to the knowledge of any person responsible for deciding whether to commence any such prosecution shall be conclusive evidence of that fact.
Subsection (1) applies in relation to offences committed on or after the day appointed for the purposes of this section by an order under section 44.