Hi Pieter,
Just checked in "ANL - A Fleet History of the Australian National Line 1957-1999", published 2020, and found that two of their unsuccessful "P"-Class ore carriers were laid up and frozen -in at Holmestrand.
The "AUSTRALIAN PURPOSE", after completion by Gotaverken Oresundsvarvet AB was laid up from some time in 1977 until being commissioned in 2/1979.
The "AUSTRALIAN PROGRESS", after completion by Blohm & Voss A.G., was laid up from about January 1978 until being commissioned in 2/1979.
So, not the "AUSTRALIAN PIONEER".
There's a photo in the book showing "AUSTRALIAN PROGRESS" frozen in at Holmestrand between three of the grey hulled Libyan tankers.

A very interesting selection of Swedish shipbuilding industry pride vessels.

Remember that "Furu" was moored to the concrete-construction bottom left for many years

A couple of corrections:
Should read "SEVONIA TEAM" (IMO: 7336410) and "ANGLIA TEAM" (IMO:7226873)
I can't find a"BRITTA" or a "MODENA" to match with any of these vessels.