4.2.1C is the latest, Wrong info from Pioneer in this thread

for users that may be confused by Jay's final answer and locking of thread, he was probably not aware there was a 4.2.1c released this week on the forum so you were right, don't go crazy, lol

last comment here - https://forums.pioneerdj.com/hc/en-us/community/posts/207903066-rekordbox-update