You can find Billinghurst cave close to Reqqa Point, you just need to drive a bit further to the corner. You will find another entry-exit point, with a ladder, right above the cave entrance. Make sure the weather conditions are good and there is no swell, otherwise the exit becomes very difficult.
In the cave you can see the exit point almost from every point, unless you swim all the way to the end. Usually cave divers place a line for training, please do not remove it. If you get disoriented, just follow it out. The bottom of the cave is 25 m, at the end you can surface, but do not breath from the air there since there is no connection to the outside.
Consider that you are in overhead environment, leave ample amount of gas to exit.
Outside the cave you find a sloping bottom, you can reach relatively quickly 45 m-50 m.
The exit point is the same spot you entered the water. This dive is classed as one of the most favorite dives of the most advanced divers.