Extension of GST notification deadlines: substituted deadlines extended and the amendment given retrospective effect to earlier notification. Amendment under section 168A of the Punjab Goods and Services Tax Act, 2017 substitutes two specified deadline date expressions in the first paragraph, clause (i), of an earlier government notification with later date expressions, thereby altering those temporal limits. The notification further declares that the amended notification is deemed to have come into force with effect from an earlier date in June 2020, giving the amended provisions retrospective commencement for implementation under the Punjab GST framework.