With the changing layout, people were asked to take extra care when travelling through the interchanges by following any temporary speed limits, traffic management and signs.
When the works were complete a 70km/h speed restriction would remain for a settling period over summer ahead of final surfacing.
People were advised to allow extra time if travelling on that section of the expressway, and merge early into a single lane to help lessen congestion.
Waka Kotahi apologised for the disruption the work was causing and thanked people for their patience.
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