First of all, congratulations for your good result. Keep up the good work!
Secondly, I had objections with your earlier scheme because it was overloaded, but this one can work fine. Of course, if you move up to finish your Chemistry and Biology A-Level next year; this, in itself, is insufficient qualification for a good Canadian university. But you can apply with this qualification--in fact, since you've studied French in IGCSE, I recommend that in your A2 your subject combination should be:
A2 CHEMISTRY, A2 BIOLOGY & AS+A2 FRENCH
French is a very important language in Canada, particularly Quebec, as you already know. It might even gain you scholarship and some preference when applying to medical schools in Canada. In general, this looks fine.
You don't
have to split your Math exams in January/March/May sessions, you can always appear in all of the components in just one--but since I'm not very well-versed in Edexcel I advise you consult your teachers or someone who is studying/had studied Edexcel. But if you don't appear for Mathematics in January, I suggest you appear for AS Biology. You'll have to memorize a lot of details but CIE AS Biology was pretty easy, so you might as well get over with it in January so you're left with only one subject concerned with memory and theory.