The Canadian Coast Guard Ship Hudson returned to Halifax Monday afternoon sporting a new red and white paint job and nearly six months behind schedule, but many questions remain about the delays.

The deep sea research vessel was supposed to return to its base at the Bedford Institute of Oceanography in May after a $4-million refit at the Heddle Marine shipyard in Hamilton, Ont.

In October, the Coast Guard towed the Hudson out of Heddle Marine before the refit was completed.

Coast Guard boss explains

In his first public statements on the troubled project, Jeffery Hutchinson, the commissioner of the Coast Guard, told a parliamentary committee last week "the work was being done and the work was generally being accepted," but delivery dates were being missed and winter was closing in.

The Coast Guard commissioner's statement suggested that weeks of work were still needed. (Robert Short/CBC)

"We had to do a very basic calculation and that is that the seaway closes on a given day and we needed the Hudson back on the East Coast before the seaway closed," Hutchinson told B.C. Conservative MP Mel Arnold, who asked why the ship was towed out of the yard with the refit unfinished.

The St. Lawrence Seaway usually closes during the last week of December to protect locks from ice damage.

Hutchinson was unable to provide a completion date, but his statement suggested that weeks of work were still needed.

Is the refit done?

The Department of Fisheries and Oceans (DFO), which oversees the Coast Guard, did not respond when asked whether the refit is now complete.

That is a question Mac Mackay is also asking. He's behind Shipfax, an insiders marine publication about what's happening in the Halifax port.

Halifax port watcher Mac Mackay is critical of how DFO handled the refit. (CBC)

"Do they have all systems working, can they take people aboard safely and go to sea and do research? Do they have all the radar, all the machinery or have they just patched enough stuff together to get it [to] Halifax?" he asked.

Mackay acknowledges repairing a 50-year-old ship is a "maintenance nightmare."

Delay not explained

DFO refused to explain what actually delayed the maintenance work, which included overhauling the superstructure and masts, blasting and recoating the hull, along with steel replacement and repairs to the rudder.

"You would think they would have investigated what repairs were needed and had a sound estimate of the time required to do it before they committed to a refit in a shipyard they know is not going to be accessible in the winter time," said Mackay.

DFO has said the original contract is being reviewed "to determine if any change to the value of the contract will be required."