You can now register as a backup! Backups will have a lot of chances to join the tournament.
Backup spots work like this (these examples assume that the tier and it's backups are full):
If a person decides to quit before or after the registrations end, the first backup in line automatically claims their spot and will of course, be notified of that.
If a person becomes ineligible to play in their tier (for example, them getting restricted or banned, ranking out of their tier in any way, etc.), the first backup in line automatically claims their spot and will of course, be notified of that.
After the registrations end, the backups do not immediately lose their chance of playing in the tournament.
On the first weekend of the tournament, when the lobbies will be played, there will obviously be people who don't show up and in cases like those, the backups can fill up the missing spots. The backups will be mentioned in #ffa-announcements on the Discord channel, and the first backup that responds with some sort of agreement that they'd like to fill the open spot, gets to do just that. This will only be possible in the first week, of course.
Good luck.