Block assessment reinstatement expands AO's power to assess extended years where unassessed assets indicate undisclosed income. The revived Chapter XIV-B reinstates a specialized block assessment framework for search cases conducted on or after September 1, 2024, requiring assessment or reassessment of the taxpayer's total income under the chapter. It empowers the Assessing Officer to extend scrutiny across multiple assessment years where indicia of unassessed assets and concealed income are present, aiming to capture undisclosed income over a defined period and prevent procedural avoidance.