For the purposes of this Part (other than section 5 of Part V.1 of Schedule V and section 10 of Part VI of that Schedule), if A - B where A is the consideration for the particular supply as otherwise determined for the purposes of this Part; and B is the total of all amounts each of which is the returnable container charge in that province for a returnable container in respect of which that consideration is paid or payable.
Where subsection (3) at any time ceases to apply to a registrant in respect of a returnable container owned by the registrant at that time and the registrant was not entitled, because of subsection (4), to claim an input tax credit in respect of the last acquisition of the container by the registrant or in respect of bringing the container into a participating province after it was last acquired, for the purposes of this Part, the registrant is deemed to have received at that time a supply of the container and to have paid at that time tax in respect of the supply equal to the basic tax content of the container at that time.