Teams to act as a PBX when using Direct Routing
It would be nice if Teams would act as a PBX when using Direct Routing and your own PBX and not send everything back down the Direct Routing Trunk to the PBX to handle, IE : Call transfers.
The only time something should come back down to the PBX is if the teams user tries to transfer to an external number on the PSTN. This should send a new invite down the Direct Routing Trunk, and Teams should bridge the call. Not relying on the PBX to do this.
Once a call is made from the PSTN down the Direct Routing Trunk to Teams, Teams should handle everything about the call and not expect the PBX to do everything!