Regarding your first question, you won't be able to do this. Notifications are seperate events, and NotificationCenter won't (and can't) merge them.
Push notifications aren't meant to deliver (much) information, hence, you cannot rely on reading the userInfo objects. For example, what would you do if the user just closes the notification alert and deletes it without reading it?
What you should do is only use Push notifications to tell your app that "something has happened". The app should then fetch the information from the server. I.e, if the user taps on the last notification, the app will still download all the information linked to all five notifications.
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