(8) 2[ An application to vary the conditions of any permit, other than a temporary permit, by the inclusion of a new route or routes or a new area or, in the case of a stage carriage permit, by increasing the 1[ number of trips above the specified maximum, or by altering the route covered by it], or in the case of a contract carriage permit or a public carrier' s permit, by increasing the number of vehicles covered by the permit, shall be treated as an application for the grant of a new permit. Provided that it shall not be necessary so to treat an application made by the holder of a stage carriage permit who provides the only service on any route or in any area to increase the frequency of the service so provided, without any increase in the number of vehicles.