Turns out the mod causing the bug/issue is the Detail by Ronyx69. I located this by disabling all my most recent mods until I found the faulty Mod. To everyone out there watch out for this incompatibility, maybe its just me or maybe its an actual issue, but I can happily say that it is resolved and I can return to my hyper realistic build. My story below, you can delete this too, doesn't matter to me really.

I hope to speak to the creator of this mod. I really enjoy this mod, its given me the capabilities to build even more complex and realistic builds than ever before.

HOWEVER, upon starting up my save file today the 16th of October 2020, I noticed that all my surfaces have disappeared. All these surfaces have been converted to PO, and one that have not remain in the game without issue.

Here is where the issue get strange. PO says there are no errors and I checked the output log which also says no errors. Last time I played the same save file was 3 days ago and I had no issues. When I open PO it shows the PO option for the surfaces but still does not show the surface. I checked if they are under the map which they are not, they are not in a layer ( my build does not have any layers), and when I copy paste with Move It it places a copy but it remains invisible. The issue only lies with surfaces, decals, props, buildings and everything else is not affected.

I tried editing these invisible surfaces only for them to turn white or inverted or something. I tried re-installing PO, all the surfaces affected and even tried saving and loading a new map and placing some surfaces to test only for them to remain invisible upon loading again.

Please help me with this weird thing, I don't even know what to call it. I know I need an output log but it does not show any issues. This "error" compromised my most detailed build to date and I am quite bummed out with this issue. Please help me out, I don't want anyone else to have this issue.