Authorisation of central tax officers as proper officers permits dual orders and bars duplicate proceedings and appellate recourse. Officers appointed under the Central Goods and Services Tax Act may be authorised to be proper officers for the Goa GST Act subject to notification conditions; where applicable, an officer issuing an order under the Goa Act shall also issue the corresponding Central Act order and inform the jurisdictional central officer, proceedings already initiated by a central proper officer bar duplicate proceedings by the state officer, and rectification, appeal and revision against state officers' orders shall not lie before central officers.