Hey! Love this mod so thanks so much!
I'm in the process of creating a modpack and happened to notice that with JAS installed there are mobs now spawning on bedrock. Mobs are spawning on top of the nether which puts more of a load on the server than I would like. Is there a way to configure mobs not spawning on certain blocks? I have been throughout the configs and can't seem to find it. Thanks!

They never spawned on bedrock.

Do mobs in vanilla no longer spawn on bedrock?