When I try to change the hatch type (via ObjectProperties tab), the selected hatch type doesn’t correspond with the actual viewport hatch. This is true of a normal hatch, and the hatches extracted from SectionPlane.
Yes, there is something going on here. The hatch in the viewport changes to the one that is selected from the list but then the selection in the list shows a different type. Is that what you are seeing as well?
Same problem here.