The California DMV online change of address form allows you to change the address on your driver license and on the registrations of three (3) vehicles all together. Pro-tip: don’t.
I submitted an address change form for 3 vehicles and only the first actually went through, which I’m now finding out about at registration renewal time. The DMV person I talked to basically said s**t happens, submit each one individually next time. And charged me 20 bucks for replacement stickers.