I suppose seeds just fall down for those players that are Retired/unable to play?
Correct.
If it's a top 8 player, eg. Mafia, he will need to confirm his seed for the DE bracket. If declines, next in line takes his seed for the DE bracket.
If it's someone 9th-32nd in group stage, they will be replaced by the next player in line. We shall have confirmed emergencies on standby, eg seeds 33-40 ready to replace if they no show on Day 1.
So even finishing 33rd-36th might be enough to play in the Grand Finale if you're lucky.
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