Heavensward CE preorders not being released in AUS???

[Felis]

Well, yes, however buying the CE gives you a "code" that allows you to download the game (so those that are waiting for their CE copies to be delivered can still get early access while it arrives). I can't imagine the code that gets sent to your inbox would be region specific.

Code and SE account are region specific. If you have an SE EU account you need the code from a EU gamebox to be able to register it to the account.
At least this is how it is with the main game.