857. Where a person is, as a consequence of his or her conviction for an offence under section 855(1) or 856(1), deemed to be subject to a disqualification order, he or she shall be deemed to be so subject to a disqualification order for a period of 5 years beginning after the date of such conviction or such other (shorter or longer) period as the court, on the application of the prosecutor or the defendant and having regard to the circumstances of the case, may order.