When the timer resumes, any houses not visited during the pause time will resume where they left off so it will be a bit of a slow trickle of houses that come back up. Any houses that were entered during the pause timer will have their time reset, but a lot of people decide to go on break and such so you'll probably see a large chunk of houses demolished around 45 days after. If you're a new buyer, you'll still have to deal with the rng buffer before before the plot is available for a fresh purchase.