leaderboards top players section

[Bashem]

Im just curious how this section works my toon bashem was the first to hit 4800 ap so was top spot on this board. Others are starting to hit it also and now im 4th. Just curious if i was the first y ive been bumped down. All the other sections have an order to them how is this section calculated? Its not in alphabetical either. Just curious if bug or how calculated is all. Thanks for any replies.

[ProSophist]

If you are tied on AP, the spot is given to the person with the most kills.