Some Structuren BoundingBoxes have a weird offset

Expected behavior

Some structures return an incorrect position of the bounding box.
The following structures usually return the bounding box too high:
Cold Ocean Ruins, WarmOcean Ruins, Beached Shipwreck, Shipwreck, Buried Treasure
The following structures usually return bounding boxes that are too low:
Jungle Pyramid, Igloo
All other structures seem to be correct.

The problem only seems to occur in newly created chunks. After a server restart, the bounding box is displayed correctly.

Observed/Actual behavior

Newly loaded chunk:

After a server restart:

Steps/models to reproduce

• Install the StructureBoundingBoxTestPlugin.
• Go to the structure described in the problem above. And see at which position the bounding box with diamond blocks is displayed.
• Restart the server and go to the same structure and the bounding box seems to be in the right place.

Plugin and Datapack List

[12:07:15 INFO]: Server Plugins (1):
[12:07:15 INFO]: Bukkit Plugins:
[12:07:15 INFO]: - StructureBoundingBoxTestPlugin

[12:07:54 INFO]: There are 3 data pack(s) enabled: [vanilla (built-in)], [file/bukkit (world)], [paper (built-in)]
[12:07:54 INFO]: There are no more data packs available

Paper version

[12:08:25 INFO]: Checking version, please wait...
[12:08:25 INFO]: This server is running Paper version 1.21-37-master@dd49fba (2024-06-24T02:08:49Z) (Implementing API version 1.21-R0.1-SNAPSHOT)
You are running the latest version

Other

No response

Use the StructureBoundingBoxTestPlugin reproduction to compare bounding boxes for the listed structures in newly created or loaded chunks and after a server restart. Verify the offset directions and determine whether all affected structures become correct after restart. Done means the bounding boxes appear at the correct positions without requiring a restart.