Bondminh, from March this year all cases might be considered by different officers who are free at that momemnt. In theory, it means that cases will be finalized faster that it was before. Honestly, it's partly true because many fresh immigrants got their PR visas in one and half months.
Regarding new mail boxes. When I uploaded the latest documents on 04/07/14 and replied to my CO to Adelaide.GSM.team6@immi.gov.au. I got the following automatic mail message:
BTW, my timelime is
03/06/14 - visa application lodged, 23/06/14 - case officer allocated, 26/06/14 - medical, 04/07/14 - PCC (the latest document).