Rena's sunken wreck is believed to have moved from its position on Astrolabe Reef, following heavy seas caused by Cyclone Lusi.
A statement released to media this afternoon said divers preparing for the next operation on the ship's accommodation block observed the position of the stern section on the reef had changed.
Divers will now spend two working days surveying the wreck to confirm changes in the ship's position.
The owner and insurer have also commissioned an ADUS (underwater sonar) survey to secure a 3D computer model of the ship's position, and confirm the extent of the movement and any effect this may have had on the structure.
The remaining bow section would also be surveyed.