Shouldn't be an issue. The knowledge you need on the exams is the same, so the study book must cover all of the relevant topics.
I haven't heard any relevant changes in the exam structure, so the revision book should be good, too. Might worth a quick check on the ACCA website, though.
I am going to do that.
According to the ACCA, there will be some slight variation, but I would highly doubt that they will examine on it because it would be incredibly unfair and stupid.
I do not understand why they are using December material for September exams. It would make much more sense to link December with March and June with September.