Adult only. Private by design.
What a no-show override does

The button is for a couple who are not both at the door. It leaves them out together.
The short answer
No-show override is a button on the check-in list. Your host invites friends. The host invites friends they'd love to have there. One private link per couple. The note says they will be left out together, and matching will be computed again for everyone who is fully checked in.
It shows on party night for a finished couple who are not both checked in. If both partners are already checked in, the button does not exclude them. Undo override puts them back on the arrival list.
Adult only. Private by design. You confirm you are 18 or older. The host still checks you in. A private no stays private.
When the button is there
On a key party or a play party it is party night, and the couple has to be finished. A couple that is not finished is already not eligible, so the override is not the control for them.
On a speed date the button can show before that finished bar, still only when they are not both checked in. Both partners checked in blocks a new override on every format.
Guests cannot check themselves in, and they cannot press this button. A co-host can use the dashboard, so a co-host can press it. They still cannot delete the party or remove the original host.
What the override is not
It is not Sit this round out. Sitting out skips one key party round for a couple who is already in the rounds. A no-show leaves the couple out of the match for the night, until you undo it.
It does not send them a speech, and it does not post their names in the group chat. The etiquette of a quiet no-show is a separate page. This button is only the list.
A night in Philadelphia can use the button. Minneapolis can too. Those cities have their own pages. The mark still lives on the party.
Leaving them out is not a reveal
All mutual-yes matches are revealed by the format the host already chose. An override does not invent a pair for the people who stayed. A one-sided yes stays hidden.
A key party shows one Play Partner at the same time, after the host starts the reveal. A play party keeps matches hidden until the host reveals them. A speed date is short rounds, then yes or no.
FAQ
What if both partners are checked in?
The override will not exclude them. The app says both partners are checked in. Undo is only for a couple already marked.
Does it leave one partner in?
No. They are left out together. Matching is computed again for everyone who is fully checked in.
Can a guest press it?
No. Only the host checks people in. A co-host can press it from the dashboard. A guest cannot.
Is this the same as sitting a round out?
No. Sitting out is one key party round. This button leaves the couple out until you undo it.
When do matches show?
All mutual-yes matches are revealed by the format. A key party shows one Play Partner at the same time, after the host starts the reveal. A play party keeps matches hidden until the host reveals them. A speed date is short rounds, then yes or no.