The Bug:

Bees frequently get stuck underneath non-full blocks, such as trapdoors or farmland. They will fly right back to their stuck position if you attempt to move them. Relogging tends to fix their stuck state temporarily.

Steps to Reproduce:

1. Build an enclosure (not necessary but helps speed up the process) for the bees.
2. Ensure the ceiling is made of a non-full block. I've tested both trapdoors and farmland, but I'm sure other blocks will work.
3. Spawn a few bees in the enclosure, and watch how they seemingly attempt to fly through the non-full ceiling, permanently locking their pathfinding to that position. 

Observed Behavior:

The bees will attempt to fly through the non-full blocks, getting them stuck until either the block is destroyed or the player relogs. Pushing the bees around will only result in them flying back to their stuck position.

Expected Behavior:

The bees happily fly around without issue in their enclosure.