Paul Carter mysteriously went missing 16 years ago and there has been sightings of him since.
His family have not seen or heard from him since he vanished on an overnight ferry heading to France in April 2007.
It was feared that Paul, then 22, might have fallen overboard.
But coastguards later disputed this claiming he would have been spotted as waters were 'calm' the night of April 20/21.
Paul, from Erdington in Birmingham, was visiting Saint-Malo to help a group of friends renovate a house but, sadly, never arrived.
His last sighting was onboard trying to find somewhere to sleep after setting off from Portsmouth, BirminghamLive reports.
He did not show up to disembark with his friends in the morning.
West Midlands Police said his disappearance was "still being treated as unexplained".
The force added that "regular reviews are carried out".
Paul has never accessed his bank account or made contact with his family.
The labourer's mum, Theresa Humphries, has never given up hope she might be reunited with her son again one day.
She previously told BirminghamLive: "I believe in a mother's instincts. I truly believe he is alive, I think I would know if he wasn't.
"After he disappeared the immediate thought was that he had gone overboard. It was my biggest fear.
"But we spoke to the coastguard and they said his body would have been found if that were the case. It was a calm stretch of water and he would have been seen."
In 2020, a woman told Paul's family she believed he was living homeless in Slough. Theresa was shown a picture of the man, who was allegedly going by the name of Paul, and admitted there was a resemblance.
But the trail went cold, with homeless shelters in the area unable to say if Paul had been there. "That was the only potential lead we have ever had since Paul disappeared," said Theresa.
"There is no closure, it's as if he vanished off the face of the earth. No one has ever wanted to take responsibility and we are at a loss on what to do next."
