Good luck with this Upgrade Project.
I am curious about One thing:
Is there a Grounding Electrode at the Meter Socket / Pole, which is bonded to the Meter Socket Enclosure / Grounded Conductor via a Grounding Electrode Conductor?
This Grounding Electrode could be either:
a. Driven Rod (AKA "Ground Rod");
or
b. Armor Clad #6 Solid Copper, stapled to one side of the Pole, extending to the buried end of the Pole (+/- 72" below grade).
I am 99.9999988543% sure there is some type of GES at the Meter Pole. Most probable option would be the #6 AC attached to the Pole, with the Driven Ground Rod coming in 2nd Place.
Nevertheless, if the System in its current configuration has:
1. A Grounding Electrode System at both the Meter Pole and the Dwelling;
and
2. The Meter Socket / Grounded Conductor is bonded to the GES at the Meter Pole;
and
3. The Main Service Panelboard at the Dwelling is bonded to the GES at the Dwelling;
and
4. There are no Metallic Conductive Paths between the Two Grounding Electrodes...
Then the setup is not a hazard issue, and is Code Compliant.
Replacement of the Service Panelboard at the Dwelling does not introduce any change in the Service Entrance Feeder - even if a Main Service Disconnect (Main Breaker) was included in, or outside the upgraded Panelboard.
The above is IMHO, however the AHJ(s) will determine Compliance per Code (NEC ((or amendments to NEC)), or ESR Manual), either of which should be available for review via printed / published Text.
-- Scott (EE)
