The Royal Commission will restart its public hearings on December 7 and its full report is due on March 31.
The ferry sank with 128 people on board as it was travelling from Nuku'alofa to Ha'apai Island in Tonga.
The inquiry, which began in Nuku'alofa in October, has heard damning evidence from a number of witnesses, including the vessel's captain, who last week said he was asleep for much of the fatal sailing and was awoken only five minutes before the ferry overturned and sank.
Captain Viliami Makahokovalu Tupuptupu said he knew the Princess Ashika was unseaworthy but sailed anyway because he relied on Tonga's Marine and Ports Division to state whether or not the vessel was safe to operate.
John Jonesse, the New Zealander who was managing director of Shipping Corporation of Polynesia, bought the 37-year-old ferry on behalf of the Tongan government, but said he never looked into the state of the vessel's hull.
Mr Jonesse will return to the witness stand on January 21, when he will have counsel to represent him.
The three commissioners are Supreme Court Justice Warwick Andrew, master mariner Michael Handfield, and naval architect Richard James.
