Late fee waiver for GST returns: selected taxpayers receive limited waiver periods for delayed GSTR-3B filings. The amendment inserts a proviso waiving the late fee payable for delayed furnishing of FORM GSTR-3B for specified tax periods and defined classes of registered persons distinguished by aggregate turnover, by granting limited waiver windows measured from the original due date; the relief applies only to the late fee component and leaves other liabilities and compliance obligations intact.