Last minute cancellations

Had a flight booked at 2:55pm on Monday July 27 and returning Fri July 8.
First Jetstar cancel my July 8 flight... ok, that's alright, they gave me a week warning before I left and I was able to reschedule to fly back on a Saturday instead.
Then... on the morning of my flight on July 27 at 1:50am, I get a text that this flight has also been cancelled. I have tours booked for the Tuesday through the rest of the week, but apparently the earliest they can get me there is Wednesday!!!!

Both flights were cancelled for "operational reasons", which tells me nothing but sounds like code for "we didn't get enough passengers so we're going to screw your over so we don't lose money"