Hi Jez!
Well, yes. If that house moves out before the new one moves in, that would be okay. Also, keep in mind to put paths over that house's land after that villager moves out, because if you don't, the villager might move into the exact same spot as the previous one. Also, you need to spread paths all over the town so that it could be certain that they would move into that spot. If you spread paths all over the town, blocking all the 3x3 spaces except the plot you want, then that would work. Good luck.