Catlins locals, friends, and neighbours of Mr Beckenridge, believed to have several aliases, including John Locke, John Robert Lundh, Knut Goran Roland Lundh and John Bradford, believe they are alive and hiding out in New Zealand.
Others think the experienced commercial helicopter pilot, who had worked in Papua New Guinea and Afghanistan, might have fled overseas.
Police, who have referred the case to the coroner, confirmed this week that they are still treating it as missing persons case.
Since March, police have received multiple sightings of the pair reported to them by members of the public across New Zealand, including Southland and Canterbury.
However, the potential leads never amounted to anything.
And this week police said there has been "no new information or confirmed reports" passed on to police in the last two months.
"Until there is a conclusion, police continue to hold hope that both Mike and John are found," a police spokesman said.
Border alerts flagged up within 24 hours of Mike's disappearance from James Hargest College's junior school in Invercargill on March 13 remain place.
Police say they have reviewed "all relevant CCTV footage" in relation to the investigation, including airports security footage, and CCTV from Tokanui Service Centre where Mr Beckenridge was captured filling up with gas in the days before his car went over the nearby cliff.
Mr Beckenridge, who was living in an upmarket Queenstown estate before disappearing, was well-known in Papua New Guinea flying circles.
Pilots recall an experienced, talented and popular commercial pilot.
Pacific Helicopters PNG chief executive Mal Smith, who has been interviewed by New Zealand police, said he knew Mr Beckenridge had been having "problems getting access to his kid but we didn't know it was to that extreme".
This week he said he hadn't heard anything about his former employee's whereabouts.
Aviation expert Peter Clark has said it would be "improbable but not impossible" to flee New Zealand by helicopter.
Despite the lack of new leads, police are yet to hand over the missing persons file to the coroner.
A police spokesman said the coroner has, however, been kept in the loop with any developments.
"Any decision to hand the file to the coroner will be done after a discussion between both parties," he said.
Mike's mother Fiona Lu again declined to speak about his disappearance.
