From the Iron Man rules:
Each Iron Man Challenge Freeroll tournament will be held on the second Saturday of the following month. The top finisher in each Freeroll (A, B, C, D) will each win the first-place prize money for their respective tournament, and face each other in a four-person Sit & Go tournament at 16:30 ET held the next day (the second Sunday of the month) where the winner will claim an additional $5,000 and earn the right to play three of Full Tilt Poker's red pros in consecutive heads-up matches at 16:30 ET on the following Saturday.