(i)30% of any sum payable to a resident, on which tax is deductible at source under Chapter XIX-B and during the tax year, such tax has not been deducted or, after deduction, has not been paid up to the due date specified in section 263(1), so, however, that—(A)where in respect of any such sum, tax is deducted in any subsequent year, or is deducted during the tax year but paid after the due date specified in section 263(1), 30% of such sum shall be allowed as a deduction in computing the income of the tax year, in which such tax has been paid;(B)where the assessee is required to and fails to deduct whole or any part of the tax under Chapter XIX-B on any such sum but he is not deemed to be an assessee in default under section 398(2), then for the purposes of this sub-clause, the assessee shall be deemed to have deducted and paid the tax on such sum on the date on which the return has been filed by the payee referred to in section 398(2);