Ghost Blocks Generated When Loading Saved Structures

When using a Structure Block to load a saved structure into the world, the process of loading the structure can sometimes create a form of "Ghost Block"

What happened is I used a Structure Block to load a 25x25 square of Grass Blocks which I had created to help with speeding up the process of flattening the land in preparation for building. After the blocks loaded, everything seemed fine. Structure Block did it's thing, terrain was updated with the 25x25 square and all seemed normal.

A couple of minutes later, I went to load a second structure and discovered that I forgot to click the Save button within the Structure Block GUI. I then traveled back to where I set the dimensions for the second structure (the one I forgot to save) and re-saved the structure. After re-saving the second structure, I returned to where I was working.

These trips involved going beyond the render limit which meant the game would commence it's normal process of unloading and reloading the chunks based on the player's position.

When the chunks containing the newly loaded structure had unloaded, some kind of glitch happened and when I returned, I found a 1 block deep rectangle shaped hole.

At this point, I assumed that I didn't allow enough time to pass in order for all the blocks to finish updating so the game appeared to "Roll Back", similar to what happens after a crash. (I've found that there's a short delay between the time the blocks are loaded into the world and when the game finishes the process of writing the changes to the world's save file.)

When I returned, I fixed the hole with the 25x25 square then left the area and reloaded the chunks to see if it was a once off issue with the game's Autosave system, something that happens occasionally. 

Upon returning, I found that the 1 block deep hole had returned but was now L-Shaped and had a small section that was 2 blocks deep. This is when I realised that there was some sort of glitch within the game, something that can be further backed up with the screenshot (see attachment) of a chicken that appeared to be "floating" when it was actually standing on the Ghost Blocks that showed up when the chunks were reloaded.

After seeing the floating chicken, I went into the inventory and got a chicken spawn egg so I could further investigate the issue. When I tried to spawn a chicken inside the hole, the chickens were being spawned on the edge of the hole or if I was more than 5 blocks away from the edge, they wouldn't spawn at all.

The Ghost Blocks caused some rather odd behaviour with the in-game audio that plays when blocks are placed or broken. Whenever I placed a block in a spot occupied by a Ghost Block, the sound effect didn't play however when I broke the same block, the sound would play, suggesting that the action of placing an actual block in a position where a Ghost Block is, the game would observe the change and update the world file accordingly while simultaneously removing the Ghost Block. 

Below is some information on the 2 structures I was using when the glitch appeared.

The first structure was a 25x25 square of Grass Blocks I had made to help speed up the process of flattening the terrain so I can build on it. This is the structure that produced the Ghost Blocks.

The second structure was a section of road located a few hundred blocks away from where I was working. This structure had no issues when loaded and was the one I had to re-save.