(1) The amount of the notional tax offset under section 961-10 is reduced by the amount in accordance with subsection (2) of this section if one or more of the following applies:
(a) paragraph 961-5(1)(c) applies during part only of the year;
(b) paragraph 961-5(1)(d) applies during part only of the year;
(c) during the whole or part of the year, 2 or more individuals contribute to the maintenance of the dependant;
(d) the dependant only meets the description of the individual covered by subparagraph 961-5(1)(c)(i) or (ii) for part of the year.
(2) The amount of a notional tax offset is reduced to an amount that, in the Commissioner's opinion, is a reasonable apportionment in the circumstances, having regard to the applicable matters referred to in paragraphs (1)(a) to (d).