New Chunks in existing world changing landscape when loaded

I am also facing similar problem.
When I get close to the so-called "version wall", that part changes and goes dark.
When I save the game and reopen the darkened part, that part is fixed.

The sculk one looks kinda cool

Ya I've been having this issue recently and it's causing a lot of lag. https://imgur.com/gallery/jreJYIO

Confirming that this bug is present on 1.19.30, when running a BDS on windows 11 and connecting with an android mobile bedrock client.

The symptoms are very close to described in the original report:

• Approach a 1.17 created chunk boundary, with the adjacent chunk not existing and created in 1.19.

• the new 1.19 chunk will initially render with a harsh boundary where heights don't align

• after about 2-20 seconds the area will flatten out and potentially render into a different biome (I saw a desert turn into an ocean and a forest biome), but the flattened chunks will go completely dark even in the middle of the day; lighting doesn't resolve itself with any torch or other lighting placement to time of day change, although placing blocks in the dark area sometimes increases light levels slightly

• rejoining the BDS instance without restarting it will still result in a dark patch shown

There is a 1.19 bug somewhere in the chunk creation/conversion engine that is resulting in light levels not updating after conversion.