Hope Island move from Melb...... advise please on Private/Public secondary schools?

We are expecting to move to Gold Coast towards then end of the year. We have teenager girls and are looking at Secondary school options. Does Hope Islands teenage population go to Helensvale high school, AB Paterson or Saint Stephens? Ideally we would like AB Paterson as our eldest will start her final years (Yr11&12) in Qld. It is hard enough settling into a new state without the added pressure of new school and the important years & making friends. She would love to know she would have neighbours who go to the same school rather than be living further away from the school in a great area but not have school friends close by. Of course, we don't even know if we can get our children into the Independent schools? Are they hard to get into on late notice - i.e.. names not down since birth? Any advise would be greatly appreciated. Thanks,
Helen