ORCHARD PARK, N.Y. — A person with direct knowledge of the move confirms to the Associated Press that defensive tackle Vernon Butler has agreed to a two-year contract with the Buffalo Bills. The person spoke to the AP on the condition of anonymity Tuesday night because the contract isn’t official until the NFL’s signing period opens Wednesday. Butler continues the trend of former Carolina Panthers joining the Bills. Buffalo general manager Brandon Beane and coach Sean McDermott both made the move from the Panthers to the Bills in 2017. Butler will join former Panthers teammate Star Lotulelei, 2019 first-round pick Ed Oliver and Harrison Phillips in Buffalo’s defensive tackle rotation.