Private — only you. Default for new drafts.
Friends — couples you follow who follow you back. Mutual relationships only.
Followers — anyone who follows you, regardless of whether you follow them.
Public — everyone, indexable by Google, eligible for editorial picks.

You can change a plan's privacy at any time, and downgrading from Public hides the plan from search results — but couples who already saved it keep their copy. Privacy applies to the plan itself; reviews and completions on the plan inherit the visibility.