I was in the same situation as you a few years ago. Don't take summer school if you're going to be working full-time. You're not going to get anything out of the class if you have to skip all/most of your classes plus you're risking the grade you have the potential of getting (because you'll be skipping and since summer courses are 'intensified,' that doesn't help either)

It would be best to visit the website or office in person if you want to make sure !