Extension of GSTR-1 filing deadline: monthly and specified quarterly filers given extended time after each tax period. Extension of the time limit for furnishing details of outward supplies in FORM GSTR-1 is ordered: monthly filers must furnish GSTR-1 in the month succeeding each tax period, while the class of registered persons required to file quarterly returns under the proviso to sub-section (1) of section 39 is granted a later day in the month succeeding such tax period. The notification takes effect prospectively and supersedes specified earlier Finance Department notifications without affecting prior actions or omissions.