NSSystemClockDidChangeNotification acts weird when app wakes up

In my app I'm registering a NSSystemClockDidChangeNotification notification in AppDelegate method application:application didFinishLaunchingWithOptions:options.

Posted whenever the system clock is changed. This can be initiated by a call to settimeofday() or the user changing values in the Date and Time Preference panel. The notification object is null. This notification does not contain a userInfo dictionary.

Month ago it was working fine, but these days every time I suspend my app, lock my iPhone and leave it 2 minutes to pass, when opening the app, the selector method is called, which is weird to me. I didn't change the system or time, I just let the device idle.

Can anyone help me understand this? I just want to execute some code when the user manually change the system time, just in that case (tried with UIApplicationSignificantTimeChangeNotification but that doesn't help).


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