callcentric

This is not the bug - it's a /22 network block. It means 4 former Class C networks - 204.11.192.0, 204.11.193.0, 204.11.194.0 and 204.11.195.0. The netmask covering a whole network block's range is 255.255.252.0. It's fine for now if you use 255.255.255.0 for simplicity because, as a matter of fact, Callcentric's SIP operations use 204.11.192.0 primarily, but that may change in future to use other networking blocks as needed - Callcentric is an ISP and has many network blocks in usage.