I'm not a lawyer, but I'll give you my opinion... Michigan is a SHALL ISSUE TO RESIDENTS ONLY. When you change your driver's license to Oregon, you are no longer a Michigan resident, and your Michigan permit is invalid. You may be able to get a Washington non-resident permit and an Oregon Resident permit, and still be able to carry in both states. Check it out with a firearms instructor in the area, or the local police. Good luck.
I don't carry a gun to kill someone. I carry a gun to avoid being a victim! Gary