Failure to deduct tax deemed as deduction when the resident payee files its return, setting the TDS payment date. Where an assessee fails to deduct tax under the TDS provisions but is not deemed an assessee in default under the first proviso to section 201(1), the assessee shall, for the purposes of the relevant sub-clause of section 40, be deemed to have deducted and paid the tax on the date of furnishing of the return of income by the resident payee, thereby determining the date for treating tax as deducted and paid when the default deeming provision does not apply.