Builder Tenix Defence began constructing the $90 million Otago in February 2005.
The vessel was scheduled to be handed over to the New Zealand Government in April 2007 and its sister ship Wellington in October that year.
In September 2008, the Minister of Defence announced the Government was entering contract negotiations with the Australia-based ship-builders after the ships failed Lloyds safety certification.
In May last year, mediation began with BAE Systems (which acquired Tenix) to resolve outstanding issues.
The main issue is that the ships are 100 tonnes overweight and no longer meet specifications to operate in Antarctic waters.
The extra weight poses potential hazards, particularly when the ships are in ice.
Because they float lower in water, the strengthened ice-belt is lower than planned, leaving unstrengthened steel plates vulnerable in icy seas.
The extra weight also means the ships will not have the capability to add extra equipment, which may affect their useful lifespan.
A Defence Force spokesman said last week contractor testing on the ships continued and it had not yet been decided when New Zealand crews would go to Melbourne to bring the vessels to New Zealand.
Discussions on remedial work required on the navy's multi-role vessel Canterbury had also not been completed, he said.
Defence Minister Wayne Mapp is in Turkey at a Nato Summit.
