(1) Where relief given to a person by virtue of section 392(1) for any year of claim is affected by a subsequent alteration of the law, or by any discontinuance of the trade or other event occurring after the end of the year, any necessary adjustment may be made, and so much of any repayment of tax as exceeded the amount repayable in the events that happened shall, if not otherwise made good, be recovered from the person by assessment under Case IV of Schedule D.
(2) For the purpose of an assessment mentioned in subsection (1), the amount of capital allowances by reference to which the repayment was made, or an appropriate part of that amount, shall be deemed to be income chargeable under Case IV of Schedule D for the year of claim and shall be included in the return of income which the person is required to make under the Income Tax Acts for that year.