any and all questions can be looked up by going here:
According to the rule book as follows:
1.5. Playoff Structure
1.5.1. In divisions of 2 teams, no playoffs will be played.
1.5.2. In divisions of 3 teams, the top two teams advance directly to finals.
1.5.3. In divisions of 6 or less teams,
184.108.40.206. The top team will advance directly to the finals, and
220.127.116.11. The 2nd and 3rd seeded teams will advance to the semifinals, where the winner will advance
to play the top team in the finals.
1.5.4. In divisions of 7 to 10 teams,
18.104.22.168. The top four teams will advance to semifinals, where
22.214.171.124.1. If two teams are advancing from two brackets, the 1st place team from one bracket will play
the 2nd place team from the other bracket, otherwise
126.96.36.199.2. The top-seeded team will play the 4th-seeded team, and the 2nd-seeded team will play the
3rd-seeded team, and
188.8.131.52. The winners of each semi-final match will play for 1st and 2nd place, and the losers of each
semi-final match will play for 3rd and 4th place, except
184.108.40.206.1. The losers of the semi-final matches in the Pro division will be awarded 3rd and 4th place
based on performance in the preliminary round, with the team ranked highest after the preliminary
round receiving 3rd place.
1.5.5. In divisions of more than 10 teams, teams will advance into a single-elimination head-to-head
seeded bracket leading to the four-team semifinals.
220.127.116.11. In divisions of 11 to 15 teams, the top six teams will advance
18.104.22.168. In divisions of 16 to 20 teams, the top eight teams will advance.
22.214.171.124. In divisions of 21 to 30 teams, the top 12 teams will advance.
126.96.36.199. In divisions of 31 to 40 teams, the top 16 teams will advance.
188.8.131.52. In divisions of 41 to 60 teams, the top 24 teams will advance.
184.108.40.206. In divisions of 61 to 80 teams, the top 32 teams will advance.
220.127.116.11. In divisions of 81 to 120 teams, the top 48 teams will advance.
18.104.22.168. In divisions of 121 to 200 teams, the top 64 teams will advance.
Basically find the number of teams for d4 once all have paid and reg is closed and there you go. as far as being opened thats a question for someone else.