As of last week I started to receive the following message when uploading a new release to the Apple Store:
Funny thing is that I wasn't able to find the 'UIApplicationExitsOnSuspend' key in the Info.plist...ITMS-90339: Deprecated Info.plist Key - The Info.plist contains a key 'UIApplicationExitsOnSuspend' in bundle myAppName [myAppName.app] that will soon be unsupported. Remove the key, rebuild your app and resubmit.
The message is received on top of the now traditional "Missing Push Notification Entitlement" and it seems it should be handled likewise, meaning: just ignore it. (It worked for me)