Symbolism, Imagery, Allegory
Why Australia?
Why not?
There's nothing really specific about the conti-country that makes it the perfect place for Alexander's escapist fantasies. Instead, it's the mere fact that Alexander doesn't seem to know a lot about the place that makes it's location all the way on the other side of the world the perfect foil for his awful day.
Everything's the opposite there, right? Summer is winter, south is colder, the toilet bowl drains counter clockwise...and bad feelings are replaced with good ones. It's like a young child's concept of a hundred being an enormous quantity, 14 being the oldest of ages, or an hour being an eternity. All Alexander seems to know about Australia is that it is far away—and that's all it needs to be.
Far away from this that-kind-of day.