KiwiRail admits it may be helping out its competition by reducing its Interislander fleet to two.
Aratere will be retired when demolition begins on its decaying dock in Picton late this year or early next, to add infrastructure for new ships.
Two new ferries are due in 2029.
KiwiRail Chief Executive Peter Reidy told Mike Hosking some passengers may opt now to travel with Bluebridge.
He says capacity is spread between the companies when one faces an issue.
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