(1A) If subsection 8G(1) applies to a person who is a full self - assessment taxpayer, the interest is payable on the excess mentioned in paragraph 8G(1)(d) for the period from the beginning of the earlier of the following days:
(a) the 30th day after the day on which the person furnishes the return of income for the year of income;
(b) the due date for payment of the assessed tax;
until the end of the day on which the first crediting occurs.
(2A) If subsection 8G(2) applies to a person who is a full self - assessment taxpayer and subsection (3) of this section does not apply, the interest is payable on the excess mentioned in paragraph 8G(2)(c) for the period from the beginning of the due date for payment of assessed tax until the end of the day on which the later crediting occurs.
(3) If:
(a) subsection 8G(2) applies; and
(b) one or more payments have been made (including any taken to have been made because of the crediting or applying of any amount) of any amounts mentioned in subparagraphs 8G(1)(d)(i) to (iii) after the first crediting and before the later crediting;
the interest is payable:
(c) on so much of the excess as is attributable to a particular payment mentioned in paragraph (b)--for the period from the beginning of the day on which the payment was made until the end of the day on which the later crediting occurs; and
(d) on so much of the excess as is not attributable to payments mentioned in paragraph (b), for the period from the beginning of the due date for payment of assessed tax until the end of the day on which the later crediting occurs.
(4) For the purposes of subsection (3), but subject to subsection (5), the excess is attributable to a particular payment to the extent that it would be set off against that payment if it were set off in succession against each of the payments in the reverse of the order in which they were made.
(5) For the purposes of subsection (4), any payment is to be disregarded to the extent that:
(a) it consists of an amount on which interest is payable under section 9; or
(b) it has been taken into account in any previous application of subsection (4) of this section in relation to a later crediting occurring before the current later crediting.