Revocation deadline extension for cancelled GST registrations: filing allowed until extended date, applicable irrespective of application status. Time to apply for revocation of cancelled registration is extended to 30 September 2021 where the original due date fell between 1 March 2020 and 31 August 2021 for registrations cancelled under the specified clauses of section 29(2). The extension applies regardless of application status: not filed, pending with the proper officer, rejected (allowing fresh filing), pending on appeal, or decided on appeal. Proper officers and appellate authorities must treat the extended timeline as applicable, and taxpayers may refile where necessary.