I've notice a strange generation bug when it comes to aquafers in this most recent snapshot. Any aquafer that generates above y=8 is fine, but it's when they get below that that things get weird. Any aquafer that has generated and reaches that level will immediately be cut off, and stone will appear from then on. Any aquafers that would have generated any lower than this are just replaced with either stone or deepslate instead of water. You can tell these are meant to be aquafers due to the unique shaping and unusually flat nature of these cave floors.

I've provided several screenshots of the occurance.