Planes missing in an assembly - just gone!

If you look at the sub-assy in the assy, you can see that I have no planes - the default planes have up and flown the coop! This is making this assy throw errors because it can't find its' mates to the defualt planes because they are gone!

I just upgraded (?) from 2011 SW to 2012 SP1.....has anyone else seen this before? Or is this a "feature-added" bug that has appeared?

SolidworksAssemblies