208. Where at any time a person becomes a registrant, the following rules apply in determining the input tax refund of the person for the first reporting period of the person ending after that time,(1) there may be included the total of any tax that became payable by the person before that time, to the extent that the tax was payable in respect of a service to be supplied to the person after that time for consumption, use or supply in the course of commercial activities of the person or was calculated on the value of consideration that is a rent, royalty or similar payment attributable to a period after that time in respect of property that is used in the course of commercial activities of the person; and
(2) there shall not be included any tax that becomes payable by the person after that time, to the extent that the tax is payable in respect of a service supplied to the person before that time or is calculated on the value of consideration that is a rent, royalty or similar payment attributable to a period before that time.