It's understood most of the trips will be undertaken at night or during off-peak traffic.
The vessel arrives from Brisbane and leaves Northport for Lyttleton on Wednesday next week.
Northport spokesman Peter Heath said containers would be off-loaded by two mobile harbour cranes which would be a slower process than would be the case if the company was equipped with container gantry cranes.
Operations will start about 2pm on Sunday and are expected to be completed around midday on Wednesday.
Northport workers will work between 6am and midnight each day due to staffing numbers and equipment capability.
Heath said patience and understanding from all involved was the key to making this ship call a success.
"This is not the way we would have chosen to introduce large-scale container handling operations at Northport. We are not yet fully equipped to manage container ships of this size on a regular basis and we have had a very short planning window.
"However, our small team is well aware of the pressures being placed on other ports around the country by the perfect storm of global, regional and national pressures on supply chains. We are motivated by the challenge and more than happy to step up to do what we can to help."
Northport chairman Murray Jagger said the small, focused team was quite excited by the challenge and that the undertaking would stretch its capability to the maximum.
"While we're quietly happy about it, we won't be shouting from the rooftops until it's all done."
Northport will review its work on Constantinos P next week to determine what it can do to help and when with its limited resources.