Time for making claim

(1) Subject to sub-section (2) of this section, a claim for relief under section 46 or 47 of this Act, shall be made within two years from the end of the year of assessment to which it relates. (2) A claim for relief under section 46 or 47 of this Act, though not made within the said period of two years, shall be admitted if made within six months from the date upon which the relevant amount of United Kingdom income tax or of Commonwealth income tax, as the case may be, has been ascertained.