You can find your draft messages in the Drafts folder on your iPhone, iPad, or iPod touch.
Draft messages on your iOS device aren't synchronized with your Microsoft Exchange server, but are stored in the Drafts folder in Mail on your iPhone, iPad, or iPod touch.
The Drafts folder is at the top of the list of folders in Mail. In this folder, you'll find draft messages that you've created and saved on your device. You can edit and send these drafts from your device at anytime.
iOS 9 supports Exchange ActiveSync (EAS) protocol EAS 16, but doesn't include Draft message synchronization.
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