While we still do not have a definite answer as to how long he has been upset with the company, we do know now that CM Punk was already contemplating a departure from WWE as early as Royal Rumble 2014. He vented to Mick Foley at the time about not being happy within the company and having trouble dealing with injuries.
After almost an entire decade working for the company, Minoru Tanaka shocked the wrestling world by opting to leave New Japan. The two sides simply were not able to come to terms on a brand new contract. There are talks that Tanaka could be headed to All Japan soon.