Need to check stores for availability.
Extra 50% off is automatically applied at check out.
ie: Nike All Court 2 comes down to $25 compared to Hype DC's sale ($50)
Edit: Call your local store to see if they will honour the 50% off, as according to this comment: https://www.ozbargain.com.au/comment/5149893/redir
they should be able to do it.
That's weird, I got a tax invoice via email from platypus + a email from paypal saying I'd sent a payment to them. Even though I got the "cant process the order" error.