Conditional waiver of late fee for delayed GSTR filings: extended deadline permits regularisation without late fee under substituted deadline. The notification substitutes the earlier final date in the proviso with a new final date of 31st day of August, 2023, extending the period for a conditional waiver of late fee for non-filers of GSTR-4 for July 2017 to FY 2021-22 where returns are filed within the extended window, and deems the amendment effective from the 30th day of June, 2023.