James Anthony Cunneen, 32, was in 2022 found guilty of being an accessory after the fact to murder over the brutal death of Ms McBride at Muswellbrook in 2014, a jury finding he knew all along what happened to the "missing" mother and helped her killer, Sayle Kenneth Newson, cover up the crime by disposing of her body and creating a false alibi.

Cunneen was later jailed for a maximum of seven-and-a-half years, with a non-parole period of four years and was not eligible for parole until 2026.

But on Wednesday morning the Court of Criminal Appeal upheld an appeal against Cunneen's conviction, quashing the guilty verdict and ordering he face a new trial.

It was unclear whether Cunneen would be applying for bail while he awaits a re-trial, which likely will not be held until 2025.

As of Friday, Cunneen remained behind bars and his matter was listed in Sydney's Downing Centre District Court on March 22 to set a new trial.

Cunneen was the second man charged over the murder of Ms McBride to have his appeal determined this month after the Court of Criminal Appeal last week ruled 2-1 in favour of dismissing both the conviction and severity appeal for Ms McBride's jealous boyfriend Sayle Newson.

Newson's lawyers have said they are eyeing a potential appeal to the High Court of Australia after the dissenting judge ruled he would have quashed the murder conviction and ordered Newson face a new trial.

Newson, now 46, was in 2021 found guilty of murdering Ms McBride, a jury left with no doubt he was the person who intercepted the 31-year-old after she left a house at Muswellbrook on September 30, 2014, and inflicted a number of blows to her head and back before dumping her body near the side of a stretch of road outside Scone.

Ms McBride's skeletal remains were not found until August, 2016.

Newson was later sentenced to a maximum of 27 years in jail, with a non-parole period of 19 years and nine months and is not eligible for parole until 2038.

Newson's lawyers had argued he should be acquitted or a new trial ordered due to what they said were errors made by the trial judge, but after reviewing the evidence the CCA were satisfied beyond reasonable doubt that Newson was guilty and was the person responsible for killing Ms McBride.

Last week's judgment was welcomed by Ms McBride's mother, Lorraine Williams, who said she was "relieved and happy" that Newson would remain where he was.