Ender Crystal not spawning in correct location (one block under the obsidian)

The End Crystal should technically be on to of the obsidian not one block underneath as the bedrock base should be on top of the tower; for all you haters out there this is every tower!:

As I was trying to defeat the end, I noticed that on some of the towers the End Crystal was not there but there was still a beam going to the End Dragon, so I went to the top of the tower and the Crystal was one block underneath the obsidian:

Steps to Reproduce:
1. Enter the End
2. Go to every tower and see for yourself