SB fire is still on VHF full time.
County fire has more SafeT use than before but still mostly VHF. They broadcast most dispatches on the SafeT dispatch and VHF dispatch at the same time. The original TGIDs for county fire were changed from when the codeplugs were frist read way back when. That said what is listed as "dispatch" (tg 12573 and being used for dispatching at the moment on 800) is probably "County fire ops" and 12571 is probably dispatch as they have been testing the automated dispatch system for a week or so. So as Milf said keep an ear out for ID changes and wildcards.
Also confirm the TGID in your scanner match whats currently on the database. When phase 4 came online we noticed early on county fire was different, and you might have the old info on the scanner.