Core notification e-mails message ambiguity

The ability to have multiple notification email recipients is great.
However it is not clear if adding an email (or emails) overrides/removes the default admin email, or if it just adds email recipients.

The “you can override this below” message seems to suggest the former. While the “Add an e-mail address” placeholder in the input might suggest the later.

To be safe I copy the default admin email in there as well. But it would be nice to have an option to only add emails and an option to completely override the email and a clear distinction between the two.