Will another 'Bubble' Episode ever be released?

There will not be another bubble episode in the foreseeable future. The sales on the last one, on which I think everyone did an excellent job, were not as good as had been hoped. That's not to say there'll never be another one, there are just no immediate plans. There are more H&A books being written however. I suppose the only thing I can say to the fans is, if you want more bubble episodes you'd better go out and buy them, because it really is a case of supply ad demand.