Honestly, most of this is a non-issue, real world. Very few, in any, HVAC guys would *want* to do a panel changeout.
It’s important to remember, the purpose of the CSLB is not the protection of the trades, but the protection of the consumer. It was formed in 1929 when California was overrun with scammers and snake oil salesmen and every kind of assorted loser who drained this way, trying to make a buck for nothing.
If an HVAC company applied for a permit for a panel change, it would get kicked back at plan check for wrong license class.
This state needs less regulation, not more. GCs are allowed to self-perform most trades, because that’s common sense. Some folks from other states can’t wrap their head around how a “GC” can pipe a house and not kill everyone in a 50 mile radius from e.coli, but it’s no different than people realizing that states with zero licensing, for any trade, don’t have a single higher incident of buildings falling over because the GC wasn’t licensed.
Half the states in this country don’t have licensing at all. It isn’t a license that protects the trade. Quality work stands out for those who want it, and those who wish to live in squalor and cut corners will do it, regulations be damned.