This manager is going to regret putting all of that in writing. He may have been on the precipice of leaving his current job, but once you send an unhinged text message to an employee, that employee will always have those words, and according to the Redditor, those messages may very well come back to haunt that manager. As we know all too well at this point, so much of management involves the trials and tribulations of scheduling. People switch shifts and cover for one another all the time. Ava…