PS Audio sent an email to existing customers (at least existing BHK 300 customers) with a special link for the pre-release site. Perhaps those "who would actually know" didn't? I can't speak to who PS Audio keeps in the loop for these sorts of things.
PS Audio BHK 600
Word on the street is that PS Audio has pre-full release offered their new BHK 600 mono blocks to existing customers. Looks like a P20 power conditioner without the display, so $0 spent on the external design and aesthetics (still ugly, unless you prefer the microwave look for your audio equipment). None the less, MSRP is $32,500.