You are missing difference between admissions snd tuition. The life long AZ resident who moves for a year after applying to medical school will be considered as a resident by an adcom and would be a good candidate for someone who will return to the home state to practice. His/her admissions states may show up as OOS, but adcom would consider them home grown. BTW, many technical OOS admissions are exactly this: someone with long ties to the state who is currently residing elsewhere
Now as for tuition purposes, that is uttely independent of admissions and may require adherence to a strict standard of technical residency requirements
Just for comparison for purposes of admissions, Texas has a state law that has led to very specific rules on residency by the Texas Education Commission that are determined by TMDSAS prior to applications being considered by schools. Most states are not nearly this strict or governed by law in this regard for admissions.