GSTR-3B Filing: monthly returns must be submitted electronically by the prescribed deadline and paid via electronic ledgers. The notification requires registered persons to furnish the return in FORM GSTR-3B for July 2018 to March 2019 electronically through the common portal on or before the twentieth day of the succeeding month. It further mandates that tax, interest, penalty, fee or other amounts declared in GSTR-3B be discharged, subject to the Act's payment provisions, by debiting the electronic cash ledger or electronic credit ledger, as applicable, not later than that filing deadline.