Why are there two places to specify alert recipients?

There are two places where you can configure an alert email recipient: in the Reports app under the Reports Users tab and in Config > Administration. The former is someone who will simply receive email alerts; the latter is an actual device administrator who will have admin UI access to the NG Firewall itself. (We include that option in the latter case thinking that someone who's administrating your NG Firewall probably wants to receive alerts by default.)

Both 'checks' are run individually, so if a user exists in both places and either Email Alerts box is checked, that user will receive email alerts.