Liability to tax of persons not observing restrictions and conditions prescribed under section 9 or notified under section 10

If any restriction or condition prescribed under section 9 or notified under section 10 is contravened or is not observed by a dealer, the sales or purchases of such dealer may, with effect from the commencement of the year in which such contravention or non-observance took place, be assessed to tax or taxes under the appropriate provisions of this Act as if the provisions of section 9 or section 10, as the case may be, did not apply to such sales or purchases.