Adaptive versus automatic when making a Multicam clip

When making a multicam clip, for the audio track parameters, as I undeestand it 'automatic' means  essentially 'match source'.  If your clips are stereo then the multicam clip will be stereo.  If dual mono source clipse, then a dual mono multicam clip.  So what does 'adaptive' mean?  (This is probably a question a newbie would ask but I can't claim to be one :-}.