via DJamer Wally:
"I'm not sure the depth chart had as much to do with this decision as failing to meet the expectations of the coach staff did, based on what I was told from a source.
This was a combination of a lot of things: Being in the dog house to some extent (doesn't sound like he was a regular there, but did struggle to meet expectations this offseason), which results in a drop on an already deep depth chart, all the while being far from home in North Carolina.
With the ability to utilize an unused redshirt without losing a year, I think signs were pointing towards this. Was more a matter of when than if he would leave from the sounds of things. I think Corey's a good kid and this isn't about a lack of character or morals with him. Some players just struggle to meet the demands."