I looked into this. It's very doable and easy. It's funny but the actual thing that annoys me is that if you want to get an A when you already have a C and M1, you then need to do the C and M1 tests again. And to be honest, the M1 written test is pretty hard (like at least 10x harder than the C). I obviously passed it on my first attempt but I definitely know people who decided to just keep their out of state motorcycle license instead.

EDIT in response to reply: I actually don't think it's obvious that if you get C, M1, and A separated by a month that you should do 1+2+3 tests but that if you get C+C separated by years you do 1+0 tests.