How does this handle things like replays that are queued dynamically during airing? For instance on a talk show there may be occasions where the host wishes to

How does this handle things like replays that are queued dynamically during airing? For instance on a talk show there may be occasions where the host wishes to replay a section of a guest interview or to pull up a clip to play while talking over it. Would the operator override an existing Part or updating a piece in a part? Typically this is handled live with EVS.