Notification amendment extends applicability to preceding financial years and postpones effective date to December under GST rules. The Government, exercising the proviso to the GST rules on the Council's recommendation, substitutes the words 'a financial year' with 'any preceding financial year from 2017-18 onwards' and replaces the date '1st day of October' with '1st day of December' in the specified notification, thereby expanding applicable prior years and postponing the effective date.