CBRS is a service that is provided during periods of intensity or episodes of need. There is a point in the provision of any rehabilitation treatment plan, in which the rehabilitation services being provided are no longer restorative in nature. A Member discharged from CBRS does not exclude the possibility that he or she may again
Another way to look at it is that the undergraduate course is aimed at training you how to use a tool (Probability for an example) while the graduate course is aimed at giveing you the foundation (theory) to develop your own tools.
Universities consider 12 credits for undergrads to be fulltime and 9 credits in grad school are fulltime. Grad school students often have funding jobs- teaching/research on top of those credits as well. Taking 12 credits per semeste rwould take 10, not 8 semesters to get 120 credits for an undergrad degree.