If you are seeing a banner while composing an email that says "Emailing external recipient(s)" your administrator has turned on a feature that helps you understand when you are emailing recipients external to your organization and that you are connected, this means we are using the most up-to-date information provided by the server to provide this warning.
If you are seeing a banner while composing an email that says "Some recipients may be external" this feature has been turned on by your administrator, but you are not syncing with the server, such as when your device is offline. In this case the app is using previous results, and possibly information provided by your admin to help give you this warning.
