Experimental:Poor generation of bedrock at some places

I am playing experimental toggle in survival trying what added.but when i go to cave i fall into void.

To reproduce-:

1)Install latest beta 1.17.30.33

2)Create new world with cave and cliffs experimental features On.

3) Go below bedrock and check it, you will find that a layer of bedrock is gone at some places.

Observed results-

There is no bedrock layer at -64 at some places.

 Expected results-

There should be a layer of bedrock with good generation . Not just like that a chunk is mined.

My seed on which i found this- 1837342461

My coordinates where i found this - -250 -70  -538