if my memory serves me right, there r no specific requirement for 1st yr... however, 2nd yr onwards, u need to do half of ur unit in adv/tsp level in order to be in adv sci...
yeah, it's 12 cp per semester, but keep in mind that it is only recommended to do 12cp at the adv level per semester this year. But next year, you have to have a minimum of 6cp per semester, and in your third year, you need to do one major at an adv level. As long as you get a credit average for everything this year, you can enrol in adv subjects next year.