The question itself is a little vague here so let's ellucidate.

Our system is a service that allows the MS Teams client to act as an Endpoint Device on a PBX or Trunk for PSTN calls.

This is where the Microsoft Phone Licence comes in, and is referred to as 'Direct Routing'. Microsoft will, pass PSTN calls to and from us to allow audio PSTN traffic to travel between the Teams Endpoint device and the Customer's PBX or Trunk.

Video Calls do not make use of Direct Routing and are routed over the Microsoft Network without touching us. This only works if the call is between 2 Teams users.

The 2 different routing options: Teams<>Teams by contact and Teams<>PSTN by number are managed by Microsoft with only the PSTN audio call being passed to us. It is therefore possible to make or receive either type of call on a Teams device but we are not involved in the transport or routing of Video calls. Nether does having us manage your PSTN<>Teams calls limit your ability to make or receive Teams<>Teams Video calls.