Opening or closing the doors in parking mode is a strong enough 'impact' to trigger the sensor as an impact event.
If the impact is soon after turning off the ignition, you will not get a notification when you start the car.
If the impact is shortly before turning on the ignition, you will not get a notification when you start the car.
Therefore the normal process of exiting and entering the vehicle will not cause the notification to appear.
I'm not sure how long the do-not-notify duration is, but my preliminary testing shows it is between 90s and 3 minutes.