This issue has been resolved and email sends from the AU should function normally.
Feature: Email Sends
Impact: Email sends from customers in our AU data center are currently experiencing longer than average processing times. Affected customers will see their email send "status" field showing as "pending" for extended periods of time before eventually being sent. This issue is currently under review by our Operations team. This announcement will be updated as more information becomes available.
Announced: 01:45 am UTC : 10/13/2017