Section 961A | Meaning of “the relevant tax year”
From legislation.gov.uk
In sections 960 and 961, “the relevant tax year” in relation to an amount of estate income, means the tax year in which the amount of estate income would be treated as arising if—
(a)the references in this Chapter to accounting periods were references to tax years, and
(b)section 950(3) (apportionment between accounting periods) were ignored.