Cura breaks interior wall in thin wall in every other layer and replaces with strange thin infill

[dodado 0]

Cura 4.6 and 4.7. I have a 38 degree overhang made with a sweep, with constant XY thickness of 2.2mm.  0.3mm layer height and 0.75mm line thickness, wall 2 line thick, with the intention for there to be 3 walls. I made the mistake of forgetting that the 5% overlap would be 0.375 for the 0.75mm line.  I was thinking 0.025 for the old nozzle with 0.5mm line.  That's why I set the overhang wall in the model to 2.2mm thick in the xy plane.  It would be better at 2.25-0.075=2.175mm.  But 2.2mm is still wider than 2.175mm, and I still have the minimum wall flow set to 40%, so the interior wall should be ok.

 

But Cura is breaking the interior wall on opposite corners, alternating every other layer to the opposite pair of corners. Then it's filling the gap with some really tiny lines. Why is this happening and how can I fix it?

Thanks