Norfolk Island flight fiasco

I would like to know the reasons for the flight fiasco for Norfolk Island. I have a staff member who went to Norfolk in the past week with friends, and every flight was affected with changes, no advice to passengers, at both Brisbane and the Norfolk ends. Saturday flights were changed from direct flights to departures via Sydney. On the way home the flight times were not advised to passengers. First flight was to depart at 6.30pm, then by accident found the flight time had been changed to 1.30am the following morning, no explanation.. the passengers were sent to a local restaurant for dinner, and were supposed to return to the airport at 11.30, however, they had just finished dinner and were advised they were returning to the airport immediately, as their flight was now leaving earlier. On arrival at the airport it was discovered that the sydney departure was cancelled and the plane was now going to Brisbane. Sydney passengers were left sitting in the airport. One passenger with a Norfolk to Brisbane sector, was told that she was now being sent to Sydney on the next flight and denied boarding even though her ticket stated Norfolk to Brisbane. Rumour has it that one of the OZjet planes on lease to Qantas is not permitted to fly due to lack of authorisation. One plane seems to being doing all departure, and pax not being advised. Please explain.