(1)This section applies if for any period or periods between—
(a)the time when the building was first used for any purpose, and
(b)the time when the residue of qualifying expenditure falls to be ascertained,
the building was not an industrial building.
(2)An amount equal to the notional writing-down allowances for the period or periods is written off at the time when the residue falls to be ascertained.
(3)The notional writing-down allowances are the allowances that would have been made for the period or periods in question (if the building had remained an industrial building), at such rate or rates as would have been appropriate having regard to any relevant sale.
(4)In subsection (3) “relevant sale” means a sale of the relevant interest as a result of which a balancing adjustment falls to be made under section 314.