I teach CCD1. I expect participants to keep up their work daily. Minimal effort = minimal benefit. If you are not committed to keep up on a daily basis you will not get full benefit. For some courses, like mine, you are also asked to take images; darks, bias, flats, science images, images to check linearity. If you get clouded out I can provide some images, but others don't require clear skies. You are asked to evaluate your images. You are expected to participate in discussions, etc. All this in a friendly and informal setting. After all, no participant in my course is going to get a raise for finishing the course or get fired for not finishing it. Amateur science is supposed to be fun not a drag. (BTW, no one fails, your name is simply not submitted as one who finished. But we do keep your money. ) Also note that all instructors are unpaid volunteers.
How much time: Over a week you would average a minimum of 1 hour/day. Some days not much, others more. Naturally this varies with course, some more. Traveling or have other commitments? I have had students who could handle the course in spite of travel and work obligations, making up work like imaging during the weekends. Others not. Depends on the person.
BTW: Its called CCD1, but mono CMOS is welcomed. Best to have photometric filters if you can manage to find them. Color CMOS needs to check with the DSLR course.