The betting operator’s liability (
"final liability" ) for betting tax for the final period is—
(a) if the betting operator does not have any previous liabilities for the final period—the adjusted betting tax amount for the betting operator for the final period; or
(b) if the total amount of the previous liabilities of the betting operator for the final period is equal to or more than the adjusted betting tax amount for the betting operator for the final period—nil; or
(c) if paragraphs (a) and (b) do not apply, the difference between—(i) the adjusted betting tax amount for the betting operator for the final period; and(ii) the total amount of the previous liabilities of the betting operator for the final period.