Did you have ground start trunks with Verizon? If so, did you convert the trunk ports over to loop start when you switched to cable? You can't just switch trunk types without doing the same within the SX50. I seriously, seriously doubt that TWC is providing ground-start.

Regardless, that wouldn't cause a timed problem. It would be all or nothing. Still, I would think that most outgoing calls are being made from a hotel at night. I don't know a huge amount about Mitel, but perhaps it allows a call for a certain amount of time before it realizes that the trunk type is wrong?

Also, the hardware that CLECs use often doesn't provide the precise 48 volt trunk voltage that is required for proper supervision. I'm going to guess that they are using an Arris box that only puts out between 24 and 32 volts on the trunk ports. If that is the case, you have an open and shut claim that it is a trouble on their end.

Ed Vaughn, MBSWWYPBX