title: Distinguish bounce and OOTO with Amazon SES
body: <p>I'm sending emails with Amazon SES and processing notifications with SNS.  I just realized that I have been processing OOTO messages as bounces and I would like to fix that so I properly distinguish the two.</p>
  
  <p>Both OOTO and bounce notifications have <code>"notificationType":"Bounce"</code>.</p>
  
  <p>There must be some other information in the notification that allows you to distinguish bounces and OOTOs, but I can't find this documented anywhere.  Has anyone figured this out?</p>