Our employees have Exchange on their iPhones and new emails show up on the lock screen before the phone is even unlocked. There are confidentiality concerns because of this and I've been tasked with disabling this on all our company iPhones. We are using an MDM server. I can disable the notification center on the lock screen. But apparently this doesn't stop these emails from showing up. I found that if I go to Settings, Notifications, Mail, Exchange, Show on Lock Screen, and turn this off, it solves the problem. However I don't know if there is a way to put this granular of a change into a profile on our MDM server to push out to the phones.