Checking around the web it seems that there are a few people that claim to still be growing BSHW in the coast range south of Monterey. Likely they still are. Most people are growing more modern indica crosses of it though, or what is called M10. M10 was supposedly developed by Sacred Seeds. But I attribute anything from Dave Watson or about the "Haze Bros" as being pure DEA spawned fiction. I was there then. There also still seems to be the schism between pure bred land race growers like myself around Big Sur, and the breed it to death with indica people out there. Bhodi does these and calls them BSHW, but it is an indica cross. BSHW was and is a pure sativa. I know several breeders in Pacific Valley just south of Big Sur that started crossing early in the 1980s. I delved into crossing indicas a few times, but the results are so variable that I went back to growing and breeding land race sativas. They are stable to start with, and I had more seeds than I could grow in a lifetime. I never dreamed that my seeds would become a rarity. Not in a million years. I just saved them because I wanted to grow weed.
From my memory, BS Holy weed was called Holy because Brother Perry? grew it originally from Zacatecas Purple seeds at one of the several religious retreats down there. Some say he crossed it with an indica early on (posted here on Mr Nice someplace) but that is the other type of BS (as in bull shyte). No one had indicas growing there that early. And I mean NO ONE. BS Holy was also said to have been named Holy because it was said to be sacred in Zacatecas where it was from. I think that story is not accurate. In Mexico weed was grown and usually drunk as an infused tea by the indio populations that revered psychoactive plants. But weed was even more illegal in Mexico and earlier than it was here, and the Catholic Church wanted nothing to do with it (and they still are a huge force in keeping weed illegal). But, the source of BSHW is likely accurate as being from Zacatecas. In an odd twist of fate, northern Mexico strains bloom and finish rather late, whereas southwest Mexico strains (Oaxaca/Guerrero/Michoacan) bloom and finish earlier, and Colombian strains bloom and finish later than north Mexico strains.
Most all Mexico land race strains were derived from hemp brought to New Spain by the Spanish as early as 1500. The hemp that the Spanish brought and cultivated was called Manila hemp, sourced from the Philippines. It differs from the hemp brought to the American colonies by the English and Dutch. One would presume that the Cannabis growing in the Philippines was sourced from SE Asia at some point in time, and retained more psychoactive genetics than the hemp brought to New Amsterdam/New England. But that is purely conjecture on my part. What happened after that is that the local populations figured out that the hemp flowers were mildly psychoactive, and they grew and bread it for those properties on small plots away from the hemp farms and away from the eyes of the Catholic Church, developing the land race Marihuana strains that evolved by the 1960s with different terpenes and cannabinoid combinations. The name "Marihuana" was also coined during that time in Mexico, but no one knows exactly where or when. Each region developed strains over time that differed in highs and became sales names in NorCal, like Zacatecas Purple, Acapulco Gold, and Panama Red. Just the way it was then. Weed was always named for where it was from and maybe an obvious attribute. All bag weed was land race then. There were no crosses available, at least until the mid to late 1970s. Certainly people started crossing much earlier in different places, but that was small and localized. I started getting really good local weed in about 1977 or so. That was still mostly pure sativa. Then things changed fast and breeders went bonkers with indicas in the 1980s.