10U.K.In any case where—
(a)section 4(2) of this Act applies to reduce the expenditure allowable as mentioned in section 3(4) of this Act in respect of an asset, and
(b)any disposal receipt is received or receivable in respect of the asset,
the amount which, apart from this paragraph, would be the amount of that receipt shall be taken to be reduced in the proportion in which the expenditure so allowable was reduced by virtue of section 4(2) of this Act.