Mail fell into two classes. First Class Mail, consisting of letters and small parcels weighing less than 8 ounces (250 g), comprised about 1.3% of all mail by weight and was dispatched from Brisbane to Port Moresby by air. Second Class Mail, consisting of newspapers and parcels, which respectively made up about 80.4% and 18.3% of mail by weight, travelled to New Guinea from Townsville by sea. It could take from one to four days for a parcel to make its way from the letterbox to the Army Post Office and three to eight days to make it to Townsville by rail. Mail could then be immediately loaded on board a ship that was in port loading, or it could wait for anything up to three weeks for the next ship to arrive. That ship might be under LHQ or USAFFE control, as the two armies had an agreement to carry each other’s mail. The voyage to New Guinea took another five to seven days.
Once there, mail destined for the 7th Division LOB Group, Rear Party and evacuees was separated. First Class Mail was forwarded to Nadzab by a daily flight, weather permitting. Second Class Mail was retained with the LOB Group until aircraft space became available. Forward of Nadzab, all mail was delivered by the 7th Division Postal Unit. In the case of undeliverable mail, letters and personal items were returned to the sender while newspapers and other items were distributed among the unit or to hospitals. The rapid build up of Australian troops in New Guinea for POSTERN brought about a corresponding increase in the volume of mail and consideration was given to halting the shipment of newspapers, a step which was not taken owing to the potentially undesirable effect on morale.
This made for slow and at times partial delivery of the Second Class Mail. Sergeant W. J. Blore of the 7th Division Postal Unit flew down to Port Moresby to see if something could be done. He returned with two planeloads. A huge pile of letters and parcels five metres long, two metres high and two metres wide consisting of 260 bags of mail weighing around 3,700 kg was deposited in a Kunai field. Sergeant Blore and other Army Postal Service personnel worked through the night to sort the pile so that it could be forwarded by air to Kaiapit, Dumpu and Bena Bena the next morning. The result was that on 9 October 1943, some diggers in the Ramu Valley received mail postmarked in Sydney on 7 October. Some 12½ special planeloads of parcels and newspapers were eventually despatched to Nadzab, weighing around 24,000 kg..