His stats suggest he has been too reliant on his defense, which is usually a recipe for future failure. It's not a big deal atm, most of us just don't want that 4MM option to be picked up.
If Buffalo isn't in the playoffs then most guys on the 40-man likely get called up. They're not going to play a whole lot, but that's usually the way it goes.
He has a 4.14 xFIP. Hasn't been striking out many, while walking quite a few. He's not getting an elite rate of groundballs, and a .214 BABIP suggests he has been getting very lucky. He's due to regress.