From the Yankee Stadium A-To-Z Guide:
Remember fans, on game days, arrive early. Yankee Stadium Gates on Babe Ruth Plaza and Gates 2 and 8, open three hours prior to the start of every home game. All fans are encouraged to arrive early to enjoy batting practice and infield workouts from select areas of the Field Level and the Bleachers; specifically, all fans may watch batting practice and infield workouts from Field Level Sections 103, 104, 105, 106, 107, 108, 109, 110, 111, 129, 130, 131, 132, 133, 134, 135 and 136 and from all Bleachers Sections. Please note, on certain game days the Yankees may elect not to take batting practice, infield workouts or both. Those fans who take advantage of the opportunity to enjoy batting practice and infield workouts from the Field Level and/or the Bleachers may remain until the players leave the field following the conclusion of the Yankees batting practice or 1 hour and 45 minutes after the Gates open. At that time, all fans will be asked to return their respective seats.
Fans are still not allowed in the Legends section, but at least the security guards won’t hound you for going into a section that you don’t belong in.