Help understanding the new control point appearances in R6

I’ve drawn a straight curve. Using rebuild, I’m adding a point count of 6. Under preview, it shows 9 and the all do not appear the same. What do the different control points mean?


Hello - the red marker shows the point of maximum deviation - not really relevant here - and the other ‘behind’ ones are the existing control points - from the input curve - presumably you had the points on when you started Rebuild.