iOS 12 Grouped Notifications

[Dormammu]

I noticed that when I have many iMessages, they're grouped by app on my lock screen -this is great.
On my iPhone X I notice that when I look at my phone, the phone unlocks, and suddenly the iMessages that were once grouped, immediately expand.

The other grouped notifications I have don't appear to do that.

Is there any way I can control this? I'd like them to stay grouped until I touch on them.

 

[Shirasaki]

I am not sure if forcing notification from messages to be grouped "by app" will solve this issue. You can give it a try as I don't have many messages to receive a day.