I recently moved my main Xbox One Edition worlds over to the new bedrock edition, and when I went to re-explore the land, I noticed a bug with the maps, where maps for the end dimension become nether maps, and nether maps become unwritable.
How to reproduce:
1. Create a world on XB1 Edition
2. Create a map in both the nether and the end
3. convert the world to the new version
4. Notice how the maps do not work correctly