Is there any way to force my initial villagers houses to become that villager's unique house?
I've heard one solution is to get that villager to leave, then invite them back using the Amiibo feature.
This isn't so much an update as it is just a fresh villager that happens to be the same, but so far that's the only way I've seen.
I've seen nothing in Isabelle's or the villager's dialogue to prompt them to change their design.