Alangirvan. The SYD-ABX-MEL services you refer to were operated by AN, not WX and were designated Air Coach services. You correctly point out no passengers were dropped off or picked up at ABX.
When the Wx was 'bad' at ABX or the flight was running late the a/c overflew ABX at cruise altitude which resulted in formal complaints from EW. A few crew did touch and go landings at ABX before the practice was outlawed by the company after customer complaints.
During a fuel dispute in the 80's an AN F27 picked up fuel at ABX which resulted in a complaint from EW to the fuelling agent.
An F27 under the command of the KMart kid (G.... S....) 'left' the runway after landing at ABX citing control problems. Engineers could not fault the a/c and further flights were event free.