PVCs are permanently established in the network and therefore do not require the use of addresses for call setup.
The maximum data rate of each non-scheduled flow is configured at call setup, and typically not changed frequently.
SIP is used as signalling for call setup and control.
These messages are transmitted in various stages of call setup and release.
Usually only the dialed digits were signaled, and only during call setup.
Your phone also uses the control channel for call setup.
There are messages defined for the call setup, the call release and the control of call features.
The return stack is separate from the data value stack, to improve the flow of call setup and returns.
The typical values of call setup mobile to mobile is around 6 Secs.
All of this would be negotiated at call setup.