Extension of GSTR return filing deadline for newly migrated taxpayers, postponing the applicable return period and final filing date. Extends the time for furnishing the return in FORM GSTR-3B for taxpayers who migrated to GST by substituting the return period to include returns up to February 2019 and moving the final date for furnishing those returns to the end of March 2019, effected by amendment to earlier Central Tax notifications under the Central Goods and Services Tax Act.