No bees in world, nest honey level don't increase

In my 1.15 test world I have two nests near to my base. In pre1 was bug MC-165173 fixed and bees finally start produce honey. But after upgrade to pre2 and later on to pre3, honey production stopped again and I can't see single bee in the world. I don't know, if they vanished or are in the nest.

 

I've searched current bugs, but could not find this issue there, so I'm creating a new one. Wish to provide more info, but don't know how.