Berryman's role in the reconquest of central New Guinea was extraordinarily important as well as diverse. His responsibilities for the planning and conduct of phase 1 of Operation Postern put him at the forefront of the Australian Army's operations. After Lae was captured and Blamey returned to Australia, Berryman was to stay on as MGGS NGF to play a significant role in the development of operations against Finschhafen and Madang. Towards the end of the campaign Berryman got his long-awaited chance at command in the SWPA, taking over II Corps (formerly I Corps) for the capture of Sattelberg and the drive on Sio and Saidor.

The Salamaua Interlude

Before Operation Postern could be launched Berryman had to deal with some problems surrounding the feint towards Salamaua that threatened the plan for the reconquest of New Guinea. The manoeuvre against Salamaua by NGF (Australian 3rd and US 41st Divisions) was designed by Blamey and Berryman to deceive the Japanese as to the offensive's real objective. In this context the role of the 3rd Division was to push on to Salamaua, without taking the town, in order to fulfil its role as a masking operation for the main assault on Lae. This was made exceptionally clear to Herring when Blamey and Berryman had outlined the plan for Postern to him in early May. This concept was, however, to be threatened when Herring became susceptible to 5th AF and GHQ's desires to take Salamaua at the earliest possible moment.