In the Notification Center in iOS 9 it was possible to group notifications per app or by time/day. In iOS 10 I don't find the setting to change this behaviour. Do someone know if it can be changed or is this setting not available any more?
I'm sorry if it doesn't answer your question. This is the first thing that I noticed as soon as I installed the new iOS 10 on my iPhone 6. I had words with the Apple support and they told me that it is no longer possible to group notifications by app with the new iOS 10. I’ve also submitted the feedback to Apple regarding this issue here: http://www.apple.com/feedback