Additional tax on updated return increases for later filings, raising proportional tax and interest obligations under the amended provision. The amendment to sub-section (3) of section 140B adds clauses providing that an updated return filed after twenty-four but before thirty-six months will attract additional income-tax equal to sixty per cent of the aggregate of tax and interest payable, and an updated return filed after thirty-six but before forty-eight months will attract additional income-tax equal to seventy per cent of the aggregate of tax and interest payable; the change takes effect from 1st April, 2025.