I have an issue where users change their email on Patreon, but it’s not been propagated back to Discourse. Any idea why this is, how I can fix it for the future, and how I can repair the desynced accounts (the emails are not editable in the admin interface)?
Yes, email addresses are not synced with Patreon. It’s by design. You can change it from user’s “Preferences” page.
Where, exactly? If I click “Admin” on a user, the email address listed is not editable.
Not in the admin side. You can find user’s “Preferences” page at URL
/u/[USERNAME]/preferences/account. You can reach it by clicking the “Preferences” menu in user’s profile page.