I would assume there are less bots in d2.
If there are 0, only 16 non playoff winners would promote out of the 16 d3 leagues.
Assuming my math is right.
I would say 20 wins and not winning playoffs is a guarantee. 19 is a toss up.
Assuming no bots are involved, there will be 20 teams demoting from II (2 automatic and 3 relegation series losers in each of the four leagues). That would leave 4 spots for teams that didn't win the playoffs in III to promote.