Tbh this is all seems like a "power move" on his part. Probably didn't like that he was told Vaughn will be up and the man at DH and as a "this is my clubhouse and nobody tells me what to do" is just sending 2 big middle fingers to the FO by sitting him often.
The guy who kept harping that he hasn’t really left the game, hates the game as is and wants to bring his own “observational analytics” is going to change within another couple weeks