Discussion here.

736. Foreign Events and Ratings. If a foreign player has a rating in his own country or from FIDE, that will be used to determine his first CFC rating. If he is inactive in Canada for a year but has a change in his foreign rating, his changed foreign rating will be used to recalculated his CFC rating.

New residents of Canada without a CFC rating are considered unrated, whether or not they have a foreign rating.