Police are investigating ways to retrieve John Beckenridge's Volkswagen Touareg from the sea near Curio Bay but the work was ''on hold'' until tomorrow or Wednesday, a police spokesman said.
Mr Beckenridge and his stepson Mike Zhao Beckenridge (11) have been missing since Friday, March 13.
Police had searched 30km of coastline and every line of inquiry had been exhausted, the spokesman said.
The car in which they were believed to be travelling was found in the sea at the bottom of a cliff in the Catlins. Police were unable to ascertain if bodies were in the car.
