ANU student here, can confirm it works with .edu.au emails How do they stop people taking advantage of the ability to create an arbitrary amount of email accounts?
It seems like they're detecting browser user agent (and possibly IP)
Getting a bunch of fresh IPs might be trickier, but you could probably wander around different WiFi access points, use the CSAIL OpenStack installation, or maybe just renew a DHCP lease a bunch.
User-agents a easy to find and change with a browser extension (or scripting).