I've confirmed a pattern between my two houses that the life 360 app only stays "in sync" with one hub at a time. If I refresh the stale one, it immediately works and breaks the other, and then vice versa of course.
I've thought of making a rule to trigger/push refresh, but as I'm driving I can't think of a trigger, other than something like Tasker calling API endpoint based on crossing a center location, but that would require my phone always tracking location and wonder if there's a more efficient manner, or if it's something that can be solved within the native built in app for life 360.