AAWhen best to start for December?

Why not start studying now? You can pace your studies if you start now. To supplement OT, I would suggest you buy an approved learning partner revision kit. Other than that, I don't think anything else would need to be purchased. OT Lectures, OT notes, practice platform, technical articles, and the revision kit is more than enough.

You can access a study planner here - there is also a link to a pdf at the bottom of the page https://www.accaglobal.com/lk/en/student/exam-support-resources/fundamentals-exams-study-resources/f8/compass-planning.html This students followed a very intensive course of study over 3 months https://opentuition.com/topic/my-approach-towards-clearing-aa-with-85 - if you want to be more relaxed - start sooner than 16 weeks before the exam. You should buy a revision kit for technically up-to-date question https://opentuition.com/25-discount-on-printed-acca-books - as well as plan to sit all the ACCA exams available in the CBE Platform.