How does the Audi A3 Lane Change Assist feature work?

I am looking to purchase an Audi A3 and want to understand how the Lane Change Assist feature works. Can someone explain the technical details of how this feature functions and what its limits are?

The Audi A3 Lane Change Assist feature uses radars in the rear bumper to detect overtaking vehicles and provide a visual warning signal in the side mirrors. It can also initiate a slight steering correction to prevent a potential collision.