Void World Checkerboard Corruption While Offline

Hello, I was working on a map and while I was offline the map corrupted. Coming back to it this is what I see (refer to image). I created this void world in 1.15.1 and have been working on it in 1.15.1. It looks like a checkerboard type corruption but theres an edge to it where it turns into normal flat lands. The cuts it makes are directly over the new formed land and cut clean through anything. Water / lava placed previously wont flow over it, buttons will float in the air, etc. If needed I can provide the world files, but I think this is a major issue as corruption is never good.