i havent seen an report on this bug before sorry if there was one

i tryed to crerate a new world with large bioms and the seed 1502272799

What I expected to happen was...:
The world should have been generated like normal

What actually happened was...:
some strange wolrd gerenation glitch with strange changing pictures of bioms and caves

Steps to Reproduce:
1.Create a new large bioms world
2. enable cheats
3. put this seed (dont know if required) 1502272799
4 Open the world