Hi Twinsnakes, thanks for the additional information.

Yes, it sounds like one hole did not have the proper orientation to it, this must have been corrected automatically during save or open. Holes are supposed to wind in the opposite direction as the outer trim boundary of a surface.

I've tried erasing those holes and drilling new ones and I can't seem to get the problem to repeat unfortunately.

I noticed the problem with extrude just a couple of weeks ago myself, where coplanar curves that had different winding directions would by default extude in opposite directions, this should be fixed in the latest patch though.

- Michael