I found a skeleton spawner wall mining and decided to make a grinder out of it, the seed that I and my friends are using was converted to 1.14 from 1.13.2. there were not any problems when we first made the switch but after a few days of playing and exploring the world we started to notice that touches places on walls would not light up the areas and mobs would spawn in those areas. this was only a minor inconvenience. but after I set up the skeleton grinder and had it going for a few hours, and one difficulty change from hard to easy the server not registers that the area around the spawner is getting sky block access.