<p>From the UMich website regarding residency status:</p>
<p>iii. Dependent Resident Student Who Remains in Michigan When Parents Leave the State. If you are a student living in Michigan with your parents and permanently domiciled in the state as defined by University Residency Classification Guidelines, you are presumed to retain resident status eligibility if your parents leave the state provided: (1) you have completed at least your junior year of high school prior to your parents’ departure, (2) you remain in Michigan, enrolled full-time in high school or an institution of higher education, and (3) you have not taken steps to establish a domicile outside Michigan or any other action inconsistent with maintaining a domicile in Michigan.</p>
<p>So, yes, the OP would still be considered instate.</p>