Schedule

Any combination of the three, or none of them — File Now is always there.

Setting	What it does
As soon as the folder changes	Watches `~/Downloads` and sweeps once things go quiet for 8 seconds
Once a day, at a time you pick	Default 00:05, so yesterday's files get filed on a quiet morning
When the app starts	Covers a scheduled run missed because the Mac was off

The Schedule pane: watch the folder, run once a day at a time you pick, and catch up when the app starts

A run that is missed while the Mac sleeps fires as soon as it wakes.

Filing only happens while the app is running. That is what Open at login on the Overview and General panes is for. Quitting Tideline really is the end of it — there is no helper process left behind to keep sweeping.

The eight quiet seconds

Watching the folder does not mean sweeping the instant something lands. A download in progress is a file growing on disk, and moving it out from under the browser is the one thing a filing app must not do. So the watcher waits for things to go quiet, and even then the skip list holds anything written to in the last 30 seconds and every partial-download extension back for another round.

Clearing is deliberately not on this list

Clearing old dated folders can join the once-a-day run, but never a folder change — so a download landing can never trigger a removal.