Saw this over on reddit so I cant take the credit (see link below) and registered for the Free Beta.
It's a Beta so maybe it should be moved to the forum, but if not, it is free access to the Beta which appears to be a stess test on their system and runs from 28/01/2016-31/01/2016.
It may take a few attempts but you will eventually get a code. It should ask for your date of birth (most people had the best result using a date in 1995), then select Australia then you should be able to select the game and hit next. It will ask for your name and email. If it comes up with enter the code, the website has taken you to the wrong page and you need to start again. It took me about 10 attempts but got through and got my code in my email.
Hope everyone enjoys because it looks like an awesome game!