Realising or writing off assets
184Cases where adjustment not required until assets realised or written off
(1)This section applies if there is a change of basis resulting from a tax adjustment affecting the calculation of any of the following amounts.
(2)The amounts are—
(a)any amount brought into account in respect of closing trading stock in the last period of account before the change of basis,
(b)any amount brought into account in respect of opening trading stock in the first period of account on the new basis, and
(c)any amount brought into account in respect of depreciation.
(3)The receipt of the trade or (as the case may be) the expense of the trade is treated as arising only when the asset to which it relates is realised or written off.