Interest rate relief for delayed GST returns introduces temporary nil-interest windows then phased interest for specified taxpayers. Temporary interest-rate rules govern delayed furnishing of FORM GSTR-3B for specified tax periods between February and July, 2020, distinguishing taxpayers by aggregate turnover and principal place of business. The amendment prescribes nil-interest grace periods for each class and tax month, followed by a reinstated interest rate for the remaining tolerance window, and is issued under the Meghalaya GST Act read with enabling provisions to substitute the first proviso of an earlier notification.