GSTR-3B filing deadlines: monthly returns due with a small-taxpayer concession; payment must be made via electronic ledgers. Prescription of monthly filing in FORM GSTR-3B for October 2020 to March 2021 requires electronic submission through the common portal by the twentieth day of the month succeeding the tax period, with a twenty-second-day concession for taxpayers with principal place in the State and turnover below the specified threshold; tax liabilities must be discharged by debiting the electronic cash or credit ledger as applicable and other amounts by debiting the electronic cash ledger on or before the filing due date.