Best judgement assessment applied where s142(1) notices during demonetisation remain unresponded; AOs to collect evidence and proceed. Where notices for return filing issued during demonetisation remained uncomplied, jurisdictional AOs will be provided updated identifying information and guidance, must invoke information gathering powers and conduct local enquiries, and proceed to frame a best judgement assessment after considering gathered material and affording the assessee an opportunity to be heard; supervisory directions from the Range Head and forwarding of material to jurisdictional AOs for identified ultimate beneficiaries are required, with completion targeted within the specified fiscal timeline.