Ideas
While waiting I've got a little workaround until we know it's fixed. Here is that the only safest world and area to have the lots with units in without big issues and minimal spawners and no plants in is Del sol Valley in the area with the celebrity homes. You know where Judith Ward lives and also Thorne and his family. There are only 4 spawners that spawns dirt piles and dig sites from what I seen. It's not a great workaround but it will do until Tuesday which should be patch day and we know from our tests that it's fully fixed since I do use s4s for my mod and sometimes checking my saves. Hope this helps. Plus that area has a 64x64 lot so that's something too. So sadly the safest area you need get famous. Maybe there are other worlds that are safe and don't have much spawners, plants and other stuff going on.