It is now possible to add more supporters to a video call. At the moment, a total of 5, including the Lumin screen user, can join the video call.
To add more supporters to a video call from the Lumin screen:
Tap on the Phone tile on your Lumin screen.
Tap on one of the Supporters you wish to video call with
Tap on the Video button.
While the call is ongoing, tap on the grey + Add Participants button
Tap on 1 or more participants you wish to add to the video call (You can choose up to 3)
Tap on Add Participants
The supporters who answer the call will be included in the group video call.