Houses/Lots Disappear

I also just encountered this issue for the first time. Bulldozed the Fern & Frond Wading Pond lot in Innisgreen, spent a few hours building on it, saved multiple times, then quit the game. Coming back the next day, the lot I built still appears in the map, but when I load in it has reverted back to the original lot. When I go back into the map after loading the lot, the image on the map has also reverted back and no longer shows my changes. For some reason the changes I made to the name of the lot and lot traits did save properly though.

This did happen in a pretty big save file with lots of custom lots and sims, and I get that the bigger the save, the more chance there is for something to go wrong. But seeing how this is kind of how the game is meant to be played and there are so many people running into this issue, I hope the Sims team can focus on solving it.