Still on 6.42 for the moment. I had all my ground forces at my capital disappear, seemingly for no reason and with no warning. The commanding officers are gone, too. All the off-world ground forces are fine, but that's 115 ground units, including four full divisions, gone without a trace.
I'm not sure when it happened. I got an announcement that four CBs finished training, and when I looked at the ground units tab that was all I had there. I restored to my annual backup and the forces were still gone. I restored to the previous year's backup and they were still there, so I could take stock and SM them back into existence, but that's a whole bunch of bonus morale down the drain.
Edit: On a side note, the title of the pop up window that appears when you click the SM-only button "Add Units" in the GU Training window is "Create Divisions" rather than "Create Battalion" or "Create Unit." It makes it seem like the unit selector is stuck on Divisional HQ or something like that.