Extension of GSTR-4 filing deadline: due date shifted to a later date for 2019-2020 returns under departmental amendment. The Nagaland Finance Department amends a prior notification to extend the due date for filing Form GSTR-4 for financial year 2019-2020 by substituting a later calendar date in the third paragraph, first proviso of the original notification, thereby changing the statutory filing deadline under the departmental order.