So it just sort of stopped? Actually weird how the "we can't swap" thing seemed like it was going to lead up to some big dramatic revelation but then... didn't
People are saying that it looks like it got axed, but I'm not sure that's the case: While the number of unfinished plot threads could be a symptom of cancellation, they could also be evidence that the author just didn't have a plan for anything and decided to call it quits before completely running out of ideas
So, an enjoyable series right up until it abruptly stops. Don't regret reading it, but I'm not sure I'd recommend it
That would be a fairly surprising super-ultra-hyper-writer's block, as there were quite a few new pairings that could be explored into a bit of depth, the author showed before that he isn't afraid of this with Akiho and Fuyumi. The logical candidates for this were both Yume/Satsuki and Ayu/Tomoyo, where both of these pairs offer different dynamics than any other pairings explored so far.
And really, even if we went with what we have now and didn't go into deeper exploration of new pairs, extending what we got and doing it in the same pace for another volume is something basically any mangaka can do, especially considering they have editors overviewing them.
I'd search for more, but my lack of fluency in Japanese kinda limits me. All I can find is that the manga ended in April and got its last tankoubon instantly (which might be usual, dunno). Won't ask Tomekichi, as that would be rude.