43(1)
Subject to any provision of the Taxes Acts prescribing a longer or shorter period, no claim for relief in respect of income tax or capital gains tax may be made more than 4 years after the end of the year of assessment to which it relates.
43(2)
A claim (including a supplementary claim) which could not have been allowed but for the making of an assessment to income tax or capital gains tax after the year of assessment to which the claim relates may be made at any time before the end of the year of assessment following that in which the assessment was made.
43(3)
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