Thanks Wayne, what do you mean by doing your own interconnection.I have a 5 year old NEM1 PV system in PG&E territory, and last year I added (2) Powerwalls. I did my own interconnection, and was able to retain NEM1. I had the option to go to NEM2, but as I was only adding storage and not adding PV, NEM2 was not mandatory. Whether Tesla will do as good a job on processing your interconnection, I can't stay.
Cheers, Wayne