Getting a head start on scheduling

Today I met with an academic advisor in the MCB department to discuss my schedule for the fall. Registration won't be open for a while, but I'm trying to think ahead so that I can keep open the possibility of doing a dual degree in CS as well as biology. It looks like I'll need to take the two tough foundational CS classes simultaneously if I want a good shot at admission to the program, so I wanted to see whether it was possible to do that and continue in the MCB sequence as scheduled and not go insane. There are two MCB classes that I'm expected to take next semester, plus an organic chemistry class. If I take that chemistry class over the summer, I could handle the remaining workload, even if I need to also take a physics class to be eligible for the CS transfer.