There has been no actual contact and the swing has been held by the striker for fear of hitting the opponent, the provisions of 8.6 apply. There was interference that the opponent was making every effort to avoid and the striker would have been able to make a good return, a let is allowed. By the time the payer in dark red is ready to strike, the ball is slightly behind him, there is space to play the shot straight, and to cross-court the player in dark red would have to flick the ball. A flicked cross-court would not hit the opponent. Therefore a let is the correct decision.