polesandzeros
... if you are going from capacity of 60 to 100 or 200 amps there may be more imbalanced current to dispose of ...This doesn’t make sense. Current isn’t disposed - it always flows back to the source. The ground rods are just safety grounds.
Additional wiring may require an extension of the earthing network for the house ...Why? If the ground rods and connections are satisfactory now, how would "additional wiring" compromise them?