I was playing in a newly created world in the currently released version

of the universal Minecraft for the Xbox One that a friend of mines made,

put in about 70+ hours and we got a lot of sheep mobs that consume all

of the Grassblocks and Tall Grass and turn them into regular Dirt Blocks.

Even though we place/have remaining Grassblocks around the Dirt Blocks,

the Dirt Blocks do not convert into Grassblocks.

Only Coarse Dirt actually converts in Grassblocks for some odd reason.

I hope this reports helps.