Just spoke to a helpful guy on the desk at AUS.
They are aware of the issues and were already looking at improving the contact details provided in the notam in the near future.
Not sure why the nearby LARS were not aware of status.
Turn out to have been a private venture by Templeman Adams, three ****s skydiving in full naval uniform (?) to claim "Highest Dinner Party" record.
So now we know.
nicely out of phase!