You know, I've just thought of something.
In the previous story arc, Sonya quit Zii's band. Now Zii and Yuki need a new bassist, and we know for a fact that it's crazy difficult to find a good one.
In this new story arc, we have a Gary/James/Tracy trainwreck in the making.
Is this just random storytelling? I don't think so. I suspect there's a continuity link between these two arcs.
I think the present storyline will end up with a furious and humiliated James dumping Tracy, and then quitting his job (saying that he can't stand being around Tracy anymore). Then, Zii and Yuki will come recruiting: "Hey, if it isn't James, who used to play bass in our old band! So you're jobless? Come with us, then! Let's restart the old band and hit it big this time!"
Yeah, because, as you may recall, "James" was indeed the bassist of their old band.
And thus, in this way, Zii will have again a complete band to challenge Angel's.