I have a sheet metal piece that has 2 configurations, a left hand and a right hand.  The right is defined by a sketch in an assembly, and the left is the mirrored body of the original with the original deleted.  My problem is that when I am in the left hand configuration the Sheet Metal Feature duplicates itself and advances the counter on rebuild.  I don't understand exactly what is causing this since I have done nothing unusual with this part.  I just noticed it when I attempted to flatten the piece in that configuration and the flatten wouldn't rebuild and the name kept changing.  Each time it  creates a new one the old one(s) is suppressed. When in left hand configuration I only see the latest one since the old body has been deleted.  When I go back to the right hand where everything has been created there is a suppressed sheet metal feature for each time I have rebuilt it.  Any explanation to this would be appreciated.  Its not an intricate part and I hadn't finished detailing it so I will just recreate it. But this is something I'd like to avoid repeating.

I've attached it to see if anyone can see if they can fix it or find a cause.  I wouldn't be suprised to find that it was something on this machine at that.