Cancellation of GST registration: one-time revocation window permitted subject to furnishing outstanding returns within prescribed timelines. Registration cancelled for failure to furnish specified returns may be revoked only after outstanding returns are furnished and amounts paid; where cancellation is from the order date, returns up to cancellation must be filed before application and returns from cancellation to revocation must be filed within thirty days of revocation. For retrospective cancellations where the portal blocks filing, a proviso allows revocation applications provided returns for the period from the effective cancellation date to revocation are filed within thirty days of the revocation order.