Feature Request: Start Show ABC scheme in Three Up layer

Need to choose start show scheme ABC оr AC or C etc for Three Up layer.
Now it starts always from A.


Layer uses for interview and in moment when show something from other layer (window capture, presentation, video etc)

The layer is used for the interview. Often at the moment when the presentation ща something (window capture, videо etc) is shown, one of the speakers starts to comment something - it is desirable to show sharply speaking speakers

ps A sufficient minimum would be to start from the ABS scheme instead of A