Summary: The pilot had submitted a flight plan for the IFR flight at 7,000 ft. The aircraft was limited to 6,000 ft on departure, and this altitude, along with the departure time and the transponder code were mentioned in the co-ordination between the tower and sector controllers. The details read back by the sector controller included 7,000 ft as the altitude. This error was not detected by the tower controller. The pilot subsequently reported maintaining 6,000 ft when contacting the sector controller.
At no time was the altitude prefixed by "amended" or any such phrase to draw attention to the different altitude. Airservices Australia advice was that there is no requirement for the use of the term "amended" when the cleared level is different from the planned level. This incident is the subject of safety deficiency action to investigate the need for the use of the term "amended".