Oh hai - yes, I do Comm/Adv. Maths. I can't really tell you everything about the course... I don't have room!
But it's a 5 year course, Honours included, and your Adv. Maths major is one of statistics, pure maths or applied - or, if your marks are high enough - you get invited to Quantitative Risk. I don't do that, and to me - it seems that Quant Risk and Actuarial are essentially the same and you may feel you're learning the same stuff (I could be wrong so probably ask around)
For Commerce you have your standard 'core' units of things like Economics and Accounting - and then an elective core that includes Accounting 1B and more in-depth stuff or other areas of Commerce like marketing. For the Science component, you have to do this subject called 'SCIF' - which is an epic bludge (I can write all day about it), where you do jigsaw puzzles and personality quizzes to try and "become a better scientist by learning about how people work" or something.