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.
When we submit a port-in request, the default date for port completion is set to 7 days. Naturally, we don't want to make customers wait this long, and approx 20 minutes after we submit the port-n request, we follow-up with a due date change request that's about 2 hours out from the port submit time.