"National shortage of bus drivers" seems to be a cover for it being cheaper to cancel services than it is to offer better jobs. I was stuck on Parramatta Rd (major road in Sydney) the other day waiting over an hour for a bus, any bus, to arrive. Thousands of cars went past. There is no shortage of people willing to "drive", only a shortage of people willing to "drive" under the conditions the companies' want.
A friend of mine trained for bus driving in NSW. They only told him the real conditions at the end of the training. Something like 12 hour days (two shifts + break in the middle at a depot). He refused the job as did most of the other trainees. This was a few years ago albeit, but I don't think they would have gotten any better.