The reason for that is autosupply has lots of bugs, not because Chem Labs are funky. I've seen Chem Labs with 40/20 carbon stored up when I placed a carbon mine next to them to avoid autosupply bugs. In your case, that the electrolysis-chem lab distance is smaller than the base-chem lab distance, and that both are disconnected from the base, are causing the problem. If you were to afterwards connect the electrolysis reactors to your base, the chem labs would no longer have 60/40 fuel.
