Extension of limitation periods for GST assessments and refunds; pandemic period excluded from limitation computation. Extends time limit for issuance of orders for recovery of unpaid or short paid tax and wrongly availed input tax credit for the 2017-18 tax period; excludes the pandemic interval from computation of limitation periods for issuance of orders for recovery of erroneous refunds and for filing refund applications; notification effective from the start of the excluded pandemic interval.