So far there hasn't been any news from Roland about the sound expansions for the BK-9 mentioned in the product decriptions. With the dissolution of Roland Europe, it appeared to take even longer until such additional sound collections might be released, and some like Diki expect mainly non-western types of sounds to be included.
Now, according to Ed Diaz from Roland in some NAMM videos presenting the FA-08/06, the SRX library will be re-released and made available on AXIAL from February as downloadable packages for the FA expansion slots.
He mentions the SRX around 0:53 in this video:
http://www.youtube.com/v/ErspQT7DtEQIMO, this makes it quite likely that, once the boards are converted into a downloadable expansion package, they could also be available for the BK-9.