GSTR-3B filing deadlines set with staggered state-wise due dates and mandatory electronic ledger payment by the return due date. GSTR-3B returns for October 2020-March 2021 must be filed electronically by staggered, state-linked due dates; generally by the 20th of the succeeding month, with later cut-offs for taxpayers below the turnover threshold in specified geographic groups. Tax liabilities must be discharged by debiting the electronic cash or electronic credit ledger as applicable, and interest, penalty, fees or other amounts must be debited from the electronic cash ledger, not later than the last date for furnishing the return, subject to the Act's payment provisions.