I’ve soon going to have a Digium TDM400P card connected to the BT PSTN with the FXO modules. There are already BT DECT phones on the line, and I intend to just use a Cisco phone with my FreePBX instance and not connect the existing phones to the FXS ports.
Would it be at all possible for, when a called has been picked up by the Cisco phone (via FreePBX), that it can be transferred back to the existing phones? For reference, a three-way conference call is already possible with the BT phone (1 external, 2 internal) but you have to pick up the target phone and press the call button.
TL;DR Is there anyway to make FreePBX ‘ring’ the line it is connected to by FXO?