Late fee waiver for certain GSTR-4 filers who submit delayed returns within a specified amnesty period. The notification inserts a proviso waiving the late fee under section 47 for registered persons who failed to furnish FORM GSTR-4 for the quarters from July 2017 to September 2018 by the due date but who furnish those returns within the specified amnesty window; the amendment is made under section 128 and modifies the earlier G.O. Ms No. 21.