After reading this post in swift forums about #if, @available and #available, I see that in this case, #if must be used... since any version of tvOS should not see the userNotificationCenter(_:didReceive:withCompletionHandler:) delegate method.

Update 2: Missed to add some details and another question :( Expiration handler doesn't get called (unlike the case with beginBackgroundTask(name:expirationHandler:))? Environment: Xcode 14.2, iOS 16.0, Debug and Release build, Console app (to check logs).

Update1: Correcting a typo New: Example: The sample background task is to count 60s in multiple of 10s. Old: Example: The sample background task is to count 10s in multiple of 10s.