Reporting of Imported Goods Regulations

12.3 The person in charge of a conveyance shall, before the time of their arrival in Canada, notify an officer by telephone at a designated customs office of any changes to information given by them under section 12.1 or 12.2, unless there are emergency circumstances, in which case the person in charge shall notify an officer at a designated customs office of any changes and of those circumstances at the time of their arrival.