Sorry i did not take into account day-light savings that just ticked over here in NZ, sorry about that. The Early check in is usually at counters 84-88 or something.
When i travelled between Nov 07-Jul 08 about a dozen times, early check in was always at 12pm (Mid day)
It may pay to give the Auckland emirates office a call
Chris - the last time i was at the airport in June flying out, i got there quite early and checked in at 12 and i got to the Lounge around 12:25pm and it was open