Working student + freelance tutoring?

I had a student assistant job at the university during the semester break and worked mostly in August. The student assistant contract is for three months and 80 hours per month, so I can maintain my student status with 20 hours per week. I worked most of the time in August, and the remaining hours are paid off through September and October, without me actively working during those hours. I also work freelance as a tutor. Now that the semester is approaching, I'm unsure if I can continue tutoring during this time, since my student assistant contract requires me to work 20 hours per week. Or does this not count, since I worked "overtime" during the semester break, which is now only paid out? I have to make sure I remain covered by student insurance.

Thank you in advance.