Choosing the right person
Only one person can be named. Three practical criteria: someone who will probably outlive you, whose e-mail address will still be valid in ten years, and who will know what to do with what they find.
It is not necessarily the person closest to you. It is the one most able to act.
Setting the delay
The delay is counted in years, months and days, with a minimum of two days. Choose it with your longest absences in mind — a trip, a hospital stay, moving house — and not your ordinary week.
Pushing the deadline back requires a Windows PC: there is no mobile app and no browser access.
The double confirmation
When you confirm this setting, nothing takes effect immediately. The values are held pending, and an e-mail asks you to confirm. The link is valid for ten minutes.
Without that click, the previous setting stays in place. It is deliberately heavier than the rest of the application: it is the only setting whose consequences are irreversible.
What the named person receives
Immediately: a courtesy message telling them that somebody trusts them. It does not say what the vault contains, and states that nothing is expected of them.
At the deadline, and only if automatic unlocking is enabled: a second e-mail containing your address, a sixteen-character backup password, and a download link. They will consult your vault without being able to change it.
A yearly review
E-mail addresses change, and so do people. If, when the day comes, the address on record no longer exists, the e-mail goes nowhere and nobody else is notified in their place.
Review this setting once a year — your birthday is a convenient marker.