Well, okay, there’s no evidence to support the K9 bit, but Outpost Gallifrey is carrying a quote from Ariel (the BBC’s in house rag) that Russel T. Davies is to write a new Sarah-Jane series for CBBC staring Elisabeth Sladen.
We’ve heard this one before (quite a lot around the time School Reunion aired) but if it’s in Ariel it has a bit of credibility. So this could be a second/third spin-off (will the K9 series make it to air first) albeit essentially a continuation of the first. But will it have K9 in it? There’s no mention of it, and the Jetix K9 Adventures series makes it unlikely, but after that scene in School Reunion with the wee cyber doggie zapping the Krillitanes, I’d definitely watch it for K9.