Dave, according to what I'm reading, and what is in the news, booster shots were not officially approved until today, even though some people, specifically those considered immunocompromised, have already rec'd boosters at private providers, mostly.
I know you were frustrated by your experience, but don't blame the gov't or SB County. Glitches happen and even at the SB County website it says the boosters, and only the Pf boosters, were approved today. SB County has done an incredible job immunizing residents. AND all this is for free.
I don't think the scheduling websites for the boosters are up to date at the moment, but Rite-Aid in Phelan says it accepts walk-in's. And, I will check back re: scheduling since there appears to be some confusion re: the boosters
I'm w/Kaiser but is costs much more in gas to go to a Kaiser facility than it does to go to Phelan, and I rec'd my initial vaccinations in Hesperia. We are so lucky to have both the vaccine and access. Gratitude is the name of the game. Thanks to the others who posted who confirmed Rite Aid is a viable choice.