From their website: Overture flights will focus on 500+ primarily transoceanic routes that benefit from supersonic speeds—such as New York to London or San Fran

From their website: Overture flights will focus on 500+ primarily transoceanic routes that benefit from supersonic speeds—such as New York to London or San Francisco to Tokyo. Overture won't generate a sonic boom over land cruising at subsonic speeds. Its passengers won't even notice breaking through the "sound barrier," which will be inaudible and uneventful.