ECN Forum Forums Code Related Discussion NEC & other Code issues Can't replace 100 amp with 65 breaker - illegal?

I would see what the AHJ says before I did anything.
Let him explain the violation to you.
If that EGC was legal at 100a, I would have a hard time saying it wouldn't be OK at half the amps.
At that distance #2 is far beyond what you would need for "voltage drop"