Return filing deadlines set for monthly GSTR-3B returns; tax liabilities must be discharged through electronic ledgers by due date. Specification requires furnishing of FORM GSTR-3B electronically through the common portal on or before the twentieth day of the succeeding month for the stated quarter; registered persons must discharge tax, interest, penalty, fees or other amounts by debiting the electronic cash ledger or electronic credit ledger, as applicable, not later than that prescribed due date.