The developer stages need their user names and email address anonymised. I did not find anything googling the subject matter. Maybe somebody developed a Drush extension for this? Any other suggestions are welcome too.
$ drush sql-sanitize -h Run sanitization operations on the current database. You can add more sanitization to this command by implementing hook_drush_sql_sync_sanitize(). Examples: drush sql-sanitize Sanitize database without modifying any passwords. --sanitize-password=no drush sql-sanitize Sanitizes database but exempts two user fields from modification. --whitelist-fields=field_biography,field _phone_number Options: --db-prefix Enable replacement of braces in sanitize queries. --db-url A Drupal 6 style database URL. E.g., mysql://root:email@example.com/db --sanitize-email The pattern for test email addresses in the sanitization operation, or "no" to keep email addresses unchanged. May contain replacement patterns %uid, %mail or %name. Example value: user+%uid@localhost --sanitize-password The password to assign to all accounts in the sanitization operation, or "no" to keep passwords unchanged. Example value: password --whitelist-fields A comma delimited list of fields exempt from sanitization. Aliases: sqlsan