Sometimes when I open my cities there are a bunch of buildings in holes. It also appears that there are a bunch of problems happening that weren't happening when I saved and closed the game the last time. For example, I opened the game today and hadn't played since yesterday, but a bunch of buildings are in holes and many have been abandoned because there's no power. This was not an issue last night when I saved and closed the game. And it didn't happen over the course of a few minutes like it usually does. At first I thought the buildings just weren't there, but they're still there down in the holes. The only way I can get them to fix themselves is to delete them so they rebuild. I don't mind the issues like power being out, but I wish I didn't have to delete a quarter of my city buildings so they aren't in those holes.
