I am having the same issue. Attached is a picture showing the pattern that is excluded and the pattern still showing up in the model. When I look at the BOM the excluded parts are not there and if I make a drawing the excluded parts do not show up either. Has anyone figured out what the problem is?
I'm not sure this is the same issue, but I have an iassembly stairway modeled that acts the same way updating the iassembly.
But when placing the iassembly child in an assembly it always depicts the correct assembly.
So, what I am trying to say is that my iassemblies do not update correctly until it is placed into an assembly.