A Class AB “Certificate for the Sale of Pesticides” that has not expired 3 April 2003 remains in force until it expires and shall correspond, with no further formality, to a Class A “Certificate for the Wholesale of Pesticides” and a Class B “Certificate for the Retail Sale of Pesticides”, Subclass B1 “Certificate for the Retail Sale of Class 1 to Class 3 Pesticides” and Subclass B2 “Certificate for the Retail Sale of Class 4 Pesticides”. (O.C. 332-2003, s. 21)