I've removed proxy-ca-on from the list of proxies, as I've found another use for the box it's running on.
From the logs I can see it wasn't used too much, but to avoid breaking things for the few people that were using it I've updated the hostname to point to the IP of the next closest box, which is proxy-us-nj (when I tested my ping times at proxy.ftelnet.ca it was only about 20ms slower, which isn't bad considering it's about 7x further away from me than proxy-ca-on was).