They can keep hawaii residency while active duty. Not sure what that benefits them….a lot of military stationed in Alaska will do that and maintain state citizenship so they can get the pipeline money
I went to Hawaii in 2016. While there I bought a random license plate for a friend. Before I could get it to him I put it on my undercover car just for grins. Turns out the plate was current on its registration and actually belonged on the same brown Ford 4 door I had it on.