The CC switches between the 3 control channels. The system uses high wattage transmitters and I've been able to pick it up in Center City Philadelphia. This is where I get the interference from the Bucks County system that uses the same frequencies.
Today there control channel is 501.7625. There single seems to be weak this weekend, I am occasionally losing there control channel all together when it is usually very strong here. also no Bucks county interruption here.