Extension of GST return filing deadlines: specified July return due dates moved forward under state notification amendment. Extension of filing deadlines for specified GST returns is effected by amending Notification No. 12/2017: the Commissioner, invoking powers under section 38(2) proviso and section 39(6) read with section 168 of the Nagaland GST Act, substitutes later due dates in the notification's table for the entries at serial numbers 2 and 3, thereby moving each listed due date forward by one calendar month; no other procedural or substantive return filing requirements are changed.