I'm quite sure that the "listed" means that you can only legally carry those guns that are on your CCW permit, which in turn are only the ones you had on the application, and that has nothing to do with whether they are on the roster of approved guns or not. Matter-of-fact, there are stories on the Internet that some pro-gun sheriff approved an AR pistol as a CCW (it is legal, as it is technically "concealable", but patently insane), and they are guaranteed not on the roster). As the roster is slowly shrinking, a large fraction of the pistols owned by people and added to CCW applications are off-roster.
Now whether the Butte county sheriff can actually add more than three or not is an interesting question. Call them and ask ... the limitation is not the application form (can always add an extra sheet to it), but it might be the automated printing process; I heard somewhere that all the actual permit cards are centrally made in Sackatomatoes, and the state DoJ is neither flexible nor pro-gun, unlike many sheriff's in rural area.
Welcome to California by the way, and congrats on being in a place where you can actually get a CCW! You do understand that as a new resident, you can bring as many off-roster handguns with you as you like (or more accurately, as many as your bank account can afford, and the weight rating of the moving van can handle)? You just have to register them one here, for a fee of only $19 for all the guns. I'm sure you know that some off-roster handguns fetch higher prices on the used market in California than buying them new in other states. Obviously, I don't want to encourage you to start illegally dealing in firearms without a license (no more than 5 sales per year, and no buying with intent to sell), but if you stock up before moving, and then find that the high cost of living in CA requires you to thin the herd a little bit, you might be pleasantly surprised, and that's not just by being able to surf and ski on the same day.