The Rule says:

"A Team's designation of a Milestone Prize Entry must be made by the Team leader. If an Entrant does not designate one Milestone Prize Entry by the applicable Milestone Prize Deadline, his/her/its Entry with the lowest prediction score on the Leaderboard will be automatically designated for judging."

However, in the "Submission" page, it says:

"Your team leader can select up to 1 submission that will be used to calculate your team's final leaderboard score. If your team leader does not select them, up to 1 entry will be chosen for your team based on your team's most recent submissions. "