An indicator is just that an indication of something. It doesn't necessarily within itself prove anything.Big jump for you to make with almost no information.
Impossible to reside anywhere the majority of the year if you live 3-4 places for 3-4 months. And a mailing address is just a place for mail.
Not rare for someone to not intend to make any place a permanent domicile.
What you put forth is a reasonable scenario where it's not clear they're a resident of any one state. However, it seems to me that as an American you should be entitled to residency in at least one state, the state where you're registered to vote at a minimum. But maybe I'm missing something.