It seems there was about 5 hours of down time for OSArch 12 Aug between 2:30am and 7:30am Sydney timezone. It was due to the /var partition disk space running out on the server.
The server is split into logical volumes. I kept the volumes small as I didn't know at the time which would I'd need to scale. Now, it seems as though the MySQL bin logs (/var/lib/mysql) were growing in size. I culled them down, a well as increased the volume size. We're now running at around 30% capacity, which a wise sysadmin once told me that's what you want your servers running at.
Sorry about that :)