Queues are back to zero.. everything back to normal.
This attack broke my terms of service....
Sorry for the downtime.
Root-cause: /var/log/syslog filled our disk up. I've increased the disk space and resolved my syslog problem to it shouldn't repeat.
Side Effects: The disk space issue also caused the CPU to spike which ate my CPU credits (classic AWS)... so I've moved to a new instance type temporarily at the cost of some bison bucks. The joy of being a sysadmin :)
Lessons learned: Monitoring didn't work since I've moved to Singapore and got a new number. I'll fix that tonight.