how the 8 hours limit work?

enable it to schedule or receive notifications for up to 8 hours after each launch
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There are three trigger types, UNCalendarNotificationTrigger, UNTimeIntervalNotificationTrigger, or UNLocationNotificationTrigger. Does it means we only can use  UNTimeIntervalNotificationTrigger and UNTimeIntervalNotificationTrigger's repeat function is invalid in App Clips? or we can use repeat but can't beyond 8 hours?
I think i have understand how 8 hours limit work.
  1. We can find "will turn off in 8 hours" under setting->app clips->"your clip"->notifications->Allow Notifications.

So the default option is iOS will turn off notification after clip launch.
2. We can request explicit permission for send notifications, if user click yes, the "will turn off in 8 hours" disappear in setting->app clips->"your clip"->notifications->Allow Notifications.
how the 8 hours limit work?
 
 
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