Don’t forget that the picture could have been taken from one of the aircraft that droped those torpedos. The rear gunner could have snapped it looking back as they banked away.
That's also true but under an assumption of if you can see them, they can see you, I wonder if such maneuver would have exposed the plane(s) to more AA than the pilot(s) preferred. However, the photo shows no real evidence of any AA so, the maneuver you describe may have been the case.