Check in for all EK flights opens -3 hrs prior to STD. Closes at -40 mins no if's, buts or maybes.
Earlier u check in, less time you wait in the queue and better choice of seat. Esp with loads across the ditch from BNE, queues can be lengthy.
As for asking for an invite into the new EK lounges in BNE or AKL - forget it. Restricted to commercial F and J pax (doesnt include those have been upgraded) and Skywards Gold (EK Freq Flyer prog) members.