I suggest addressing this concern by treating year 11 and year 12 separately. As you are likely aware, no assessment tasks/exams in year 11 count towards your HSC results or ATAR. Because of this, you may choose to keep tutoring in year 11. If you feel that despite the fact that none of your year 11 assessment tasks/exams will count towards your year 12 results or ATAR, you want to take year 11 seriously and perform favourably in your second last year of school, a good approach would be to establish a balance between the time allocations with respect to your tutoring services and your year 11 studies. You may wish to keep tutoring for the same number of hours per week as you commence year 11. Subsequently, depending on the workload in addition to your study goals relevant to year 11, you could either increase, decrease, or make no changes to the number of hours that you tutor each week.
Regarding year 12, this is where all of your assessment tasks/exams will count towards your HSC results and ATAR. Generally speaking, students who wish to achieve favourable results in their final year of school, the purpose of which is typically to receive an offer to study their desired degree(s) at university, may be advised not to work in year 12 and instead focus their efforts on their studies, so as to not cause any distractions or lead to a lack of sufficient study time. In the case of a student who wishes to study medicine beyond year 12, I believe that the aforementioned advice would be more relevant, especially considering the fact that while a 99+ ATAR is definitely achievable (provided you are a determined and diligent student), it is not an easy target, and will require sustained effort throughout year 12. Additionally, depending on the university(ies) to which you wish to apply, you may be required to sit and achieve a favourable result in the UCAT. Consequently, additional time will be required in order to effectively prepare for and perform well in this test.
Of course, it is important that you experience a bit of year 12 as this will assist you in making an informed decision regarding whether to keep or stop tutoring. Once year 12 begins, you will be able to determine whether continuing to provide your tutoring services will be compatible with the year 12 workload, your ATAR aim and your university study aim. You may for instance find that you have some free time during the week as a year 12 student, which you may choose to use to deliver your lessons.
I hope this helps!
