Caves and caverns seem to carve through bedrock (except the lowest layer) if the bedrock layers setting is larger than 1 and flatten bedrock is set to false. This is a very minor issue, but i personally prefer my bedrock layers to not be flat.

Pictures:

This will be fixed in the next release, v1.12.2-1.5.1

Btw, just wanted to point out that the Bedrock Layer Width setting doesn't actually do anything if Flatten Bedrock is disabled.

Thanks for pointing this out. The bedrock flattening/mining in Better Caves admittedly received minimal testing. I'll be sure to take a look.