The latest rumor floating around is that the Sisters of Battle will not be a standard codex release. Personally I find it hard to beleive, but it is possible. I am not going to get into any speculation of this rumor, and instead just get right down into it.
This rumor comes from Blood of Kittens. For some reason, there site has been taken down, and is not operational at the time of this posting, so I will update possibly later. Take with salt.
Via Blood of Kittens Tasty Taste
I want to confirm for everyone that the Sisters new ”book” will be coming out sometime this year (most likely before the Necron release). There is more– SoB will be White Dwarf only release stretched over two issues, with a online PDF by the end of the year. I had reported this possibility (in a cryptic matter before) on BoLS, so this is a confirmation of said rumor. Cruddace will be your GW author for this book. No word on new sculpts, but my bet is on only resin recast of existing models. As for the rules I have nothing to report as of yet, but look for at least two ecclesiastical characters from the fluff/past to appear in the new dex.
Rumors have it that the site may be down due to trying to leak pages from an upcoming codex. This is also a rumor, so don't beleive it til more information comes out.
a memo was given to people legal action was going to be directed towards certain sites
BoK was one of them