(1) This section shall apply where pursuant to an application under section 1023 a husband and wife are assessed to tax for a year of assessment in accordance with that section.
(a) Subject to subsection (3), the benefit flowing from the personal reliefs for a year of assessment may be given either by means of reduction of the amount of the tax to be paid or by repayment of any excess of tax which has been paid, or by both of those means, as the case requires, and shall be allocated to the husband and the wife, in so far as it flows from -
(i) relief under sections 244, 372RA and 372AAB, in the proportions in which they incurred the expenditure giving rise to the relief;
(ii) relief under sections 461, 464, 465 (other than subsection (3)) and 468, in the proportions of one-half and one-half;
(iii) relief in respect of a child under section 465(3) and relief in respect of a dependent relative under section 466, to the husband or to the wife according as he or she maintains the child
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