Idk what the format is gonna be but it has to be Swiss right? Right? Right????? I swear if Riot does groups it's gonna be a fucking shitshow cause they are gonna do em full random since there's no seeding yet
Apparently there are rules in Chess for Swiss tournaments with an odd number of players, so they could theoretically break it down like this:
30
15 15
8 15 7
4 12 11 3
4 6 12 5 3
4 6 6 6 5 3
Assuming initial matches are Bo1 and your qualifying/elimination matches are Bo3, I believe this would be 47 Bo1 and 24 Bo3 matches, with 5 teams receiving one BYE at some point in the stage.
This also has the advantage of dividing the field into 16 winners and 14 losers, so you can easily set up the following stage of the tournament.