Huge chunks rendered invisible after leaving the nether

Before entering the nether, the game runs smoothly and the nether loads fine:

However, on leaving the nether, the first noticeable issue is that the 'building terrain' screen is visible for much longer than usual, as if the world is taking longer to load. Once the terrain has been built, and the screen returns to normal, huge chunks of the world are missing/invisible:

I can still interact with the blocks, but they are completely invisible. I can see through the world and into caves below:

This only seems to affect one very specific (but very large) area of the world. The issue is present in both survival and creative modes.

I have only noticed this bug since the release of the latest update. I have tried uninstalling and reinstalling the game, checking for new updates, and changing my graphical settings, however nothing works.

I even double checked, and retested for the issue in a completely new world in both survival and creative modes, and the issue still persists!

I would be really grateful for any help on the matter!