In the case of a category 1 or 2 offence that is a continuing offence, the time for filing a charging document must be determined under subsection (3) by reference to the maximum fine that may be imposed for the initial offending (or, if there is no separate fine prescribed for the initial offending, the fine prescribed for each day or each instance of offending) without taking into account the amount of any further fines that may be imposed as a result of the offence continuing.