sinophile888, no I do not, but there are three most likely possible causes that you have hit on the head: (a) lack of bookings (b) an aircraft having gone unserviceable (c) lack of either sufficient flight or cabin crew.
Of course there is also the 'X factor' with something else.
Unfortunately for JQ they are now less reliable (by that I mean 'more likely to cancel a flight') than any of the other three mainline domestic airlines on the MEL - PER run, and less punctual (and by a wide margin) than the other three on our busiest domestic air route and in the top five most well patronised in the world, MEL - SYD.
Just why they are cancelling MEL - PER flights but leaving SYD - PER unscathed is beyond me, although since MEL - PER carries more passengers than SYD - PER and would have had more individual flights, it may be that it is easier for JQ to shunt any passengers who booked on these flights onto its stablemate QF's offerings and save a lot of money by not operating return trips to PER.
Mining related fly-in, fly-out bookings to and from PER must have dropped along with the closure or temporary mothballing, or staff reductions at iron ore mines but I would have though most of these 'business but 'HI-Vis vest equipped' employees would use QF, and to a lesser extent VA.
If suburban or country rail, tram or bus operators consistently cancelled the same trips and effectively reduced their schedules by at least 25 per cent, there would be community outrage, emails and letters to parliamentarians, media articles and the like.
When airlines cancel flights in a pattern like this, there is relative silence (although since not many who look at AFF seem to travel on JQ or TT), the lack of input is understandable.
If you do find out the 'reason', sinophile888, please inform us all as I for one would like to know.
One 'cost' to travellers like you is that with fewer flights across the four airlines between MEL - PER - MEL, in theory it is easier for fares to rise, provided of course that the airlines believe that they can still operate at an acceptable yield should demand decrease even more. Some market segments such as leisure travellers can be discretionary and hence have a degree of price (fare) sensitivity.
PER is a wonderful place with for instance plants that will not grow well elsewhere in Australia (unique) but it is also allegedly the most geographically isolated urban agglomeration on earth, so many of you Perthites and general Sandgropers must feel a need if you can afford the fare and time to visit the 'eastern states.'
Why don't you consider contacting a journalist at 'The West Australian' to ask some questions of JQ? It's about time this company was held to account as you and others are suffering from fewer choices in travel, and on top of that the expensive leisure alternative of 'The Indian Pacific' train is running (or perhaps about to run) less frequently to and from Perth. I mention that as an aside because it is yet another example of the 'transport isolation' of the West, our best performing (historically) Australian state in terms of export revenues for Australia.
UPDATE: JQ502 to which I referred in a previous post as likely to depart MEL 90 minutes late with VH-VGH is now an expected two hours late (1055) into SYD. This shows how in MEL these anticipated delays can build. Inevitably other flights will now be late all day.
