It is Dutch Ashkenazi, and has more of a firm basis in halocha than even 3 hours. I can’t remember the exact mekor, but it is easy to find right there in the beginning of Shulchan aruch yoreh deah.
The kehilla in Holland still keep it, as well as many Dutch descended Jews.
LB, to answer your question; I think it is like standing or sitting for Kiddush, or washing before or after kiddush. A minhag goes after the husband generally, and doesn’t matter where you end up in the world.