My understanding:
PRS has continually offered Brazilian, and it hasn't been illegal per se as long as it's not an import or export.
CITES requires clear documentation in order to move the wood in or out of the US (and other participating countries, presumably). It sounds like CITES documentation is a pain in the arse, and thus why recent guitars with Brazilian are labelled on the headstock and sold as "USA only".
My guess is that either PRS has a limited stock of Brazilian that does have existing CITES documentation, or they've just sucked it up and went through the hassle with the very limited number of exported Bernies... Just a guess tho. Maybe they'll swap the Brazilian for Indian or mahogany and make that the PS model. Or maybe it'll just be the 6?
And is it just me, or is waiting for NAMM pretty painful? ;-)