How does Vapi / Twilio work with mobile phones? My client has an AT&T mobile phone probably android or apple, I know to use Vapi I need to port the number to Twilio but will that cause them to lose data services and such like 5G/LTE for example? What is the best way to go about this? I'm sure they will also want some control like being able to stop the AI if needed and I'm not available to do it