Yes, there is still a random timer.
I would also recommend interacting with the house. I know that people who are in the Interior Design Contest are not allowed to move items around or change their estate, so what I’ve been doing is taking a few things out of storage, dropping them into my inventory, and then putting them back in storage. I’m also talking to the Junkmonger NPC every day, purchasing either a random Dark Matter or selling useless stuff to them. Just so my house has me interacting with it, and not just me stepping into it. I’m doing the same with the FC house I own.
I’m also making a point to idle in there (my personal) longer than I usually do. Even if the bug is isolated, I’m doing what I can to make sure I’m not affected, because I have Plot 41 in the Lavender Beds that I secured after the new Wards were added (dream plot), and I would cry if I lost it. ;_; I’m checking my Timers daily, and if I see a demolition timer appear, I’m immediately going to contact Support and talk to them while I’m standing in my house (especially if the timer doesn’t disappear). I will not lose my house to a bug or error. ;_;