Additional tax on updated returns increases with delay; late updates barred after three years if a Section 148A notice exists. The e-Verification Scheme 2021 charges an additional tax on an updated return, rising by prescribed percentage bands the later the return is filed after the relevant assessment year, applied to total tax and interest payable. Filing an updated return is barred after thirty-six months from the end of the relevant assessment year if a Section 148A notice has been issued, but remains possible if the Assessing Officer subsequently issues an order under Section 148A(3) declaring the case not fit for reassessment.