"these early production A380's are a little over weight"
Exactly this. It's entirely expected that the first 6 out the door would retire early thanks to their extensive rewiring jobs and additional tweakage. They're more than just a little overweight.
Airbus made a grave mistake freezing and then cancelling A380F rollout in favour of getting the passenger versions fixed. The freighters could have been flying and generating income for a couple of years earlier than the passenger version, but instead all the freighter customers jumped ship and went elsewhere.