What does ttyUSB mean? Sometimes, the embedded microcontroller does not come with a hardware USB interface. While it is possible to use a software-only USB stack, the additional constraints put onto the CPU and the usually small storage size often lead board designers to include a dedicated UART to USB bridge.
Because of a busy weekend I didn't really follow up other than via emails and this still hasn't been resolved. The consistent word from them was that porting a number sometimes takes 24 to 48 hours.. I spoke to a rep by phone today who promised it would be done within 2 to 4 hours.. It wasn't.
System default setting is 30 (32) seconds = 8 rings assuming your phone is on and in touch with the network, if not, the call will usually go directly to voicemail with no rings. You can request a shorter period of time. I have found that 20 seconds is about right in the professional world. This setting yields 4 rings. If you have a ported number, you caller might hear a split ring before the first Verizon ring. In that case it can be 5 rings with a 20 second setting. Under most conditions, a 20 second setting will equate to about 14 seconds of actual ringing on your phone. This takes into account the slot cycle and the porting issue.