Apart from the hybrid paper, where can we find the September and December 2015 past Q papers and answers to them?
You can get the exam question and answer from this link depending on which variant:
Both exams diets have be collapsed into one. So the Q&A on acca site is for both diets
Use the examiners report to work out what style of questions were asked in the September exam.
That should allow you to work out from the consolidated exam what questions relate to September.