this is the field help - Indicate the users in your account who should receive email copies of this bundle’s messages. Default choice is All Bundle Admins, indicating that all administrators and users with the SuiteBundler permission in your account receive bundle messages as email. Choose None to indicate that bundle messages should not be sent as email to anyone in your account. Choose Custom to indicate that bundle messages should be sent as email only to selected bundle administrators, then click the Edit List link to select them.