The Corbett family will urge North Carolina prosecutors to arrange the retrial as a matter of urgency – warning that ongoing legal delays have been "an absolute nightmare" for Mr Corbett's two orphaned children, Jack (17) and Sarah (15).
Judge David Hall will stage a pre-trial hearing with prosecutors and defence attorneys in Lexington, Davidson County on September 21 next in respect of the retrial.
That hearing will be staged six months after a preliminary retrial hearing last March – and four months after a trial date was originally supposed to be confirmed.
Independent.ie has confirmed that three members of the Corbett family – Jason's three siblings Tracey, Marilyn and Wayne – have written this week to the Davidson County District Attorney Garry Frank seeking clarification about the September 21 hearing.
Tracey Corbett-Lynch – who has spearheaded the campaign for justice for her brother – declined to comment on the matter for legal reasons.
She is expected to be a witness at the retrial.
However, a family spokesperson confirmed that family members will travel to North Carolina for the September 21 hearing - and want a commitment to a retrial date in October or November.
This would enable the retrial to be concluded before Christmas.
"Our priority is to see justice done for Jason and to protect his two children. This legal process has been hanging over the heads of Jack and Sarah for seven years now since their father was murdered (in 2015) and they were made orphans," the spokesperson said.
"It is simply not acceptable for a retrial to be staged in 2023 by which time Jason's killers will be walking free from their prison sentences for two years.
"Justice delayed is justice denied. That is the message we will be bringing to North Carolina next month.
"We want to once again stress that we have full faith in North Carolina prosecutors and the US justice system. We will not rest until justice is done for Jason."
Mr Corbett's Limerick-based family pleaded for the situation over the retrial to be clarified after they had been in the dark since March over precisely when it would be staged.
The family were so desperate for information they enlisted the aid of Foreign Affairs Minister Simon Coveney and the Department of Foreign Affairs.
Their concerns are underpinned by the fact Jack and Sarah are facing examination years in Ireland, with Jack scheduled to sit his Leaving Cert.
Family members believe that the ongoing trial delays have been deeply unfair to the two children who, unlike in the original 2017 trial, will now give evidence.
Mr Corbett's two children came face to face at the March hearing with their stepmother and step-grandfather for the first time since their father was beaten to death in the bedroom of his North Carolina home in August 2015.
Their father, a packaging industry executive, was beaten to death in his bedroom with a concrete brick and a metal baseball bat.
The 2017 trial heard that an attempt had been made to drug him, and he was beaten even after he was dead. Tom and Molly Martens then delayed calling emergency services to ensure he was dead when they arrived.
Mr Corbett, who was a widower, had refused to sign adoption papers to allow his American second wife equal rights to his two children.
His family are adamant he was killed because he was about to bring his two children back to Ireland amid increasing concerns over his wife's mental health and increasingly bizarre behaviour.
Judge Hall of Forsyth County, who was specially appointed to hear the retrial, has already warned both prosecution and defence teams that no comment can be made to the media in relation to the case without his approval.
Judge Hall is a former prosecutor.
"This case has garnered, it is fair to say, a tremendous amount of media coverage by what I consider the news media and what I consider the entertainment media," Judge Hall said.
He said his priority was to ensure that justice was served – and the rights of the media would have to be balanced against that.
Judge Hall made an order specifically prohibiting either the prosecution or defence legal teams, or any of their staff or agents, from making any extra-judicial statements about the case.
He also said he would not allow what he termed any "media exploitation" to undermine the operation of the justice system.
"My only rule is to see these parties receive a fair trial without any external forces in play. We are here for one purpose and that is to serve justice."
Mr Martens, a former FBI agent, and his daughter, Molly, were convicted in August 2017 after a five-week trial of the second-degree murder of Jason Corbett and sentenced to 20-25 years in prison.
However, they subsequently won a retrial after a challenge to the North Carolina Court of Appeal and then North Carolina Supreme Court.
Both served three-and-a-half years in prison before being freed early last year.
The father and daughter insisted they only acted in self-defence and that Mr Corbett had attacked his wife.
However, while both Tom and Molly Martens were found totally uninjured at the scene, Mr Corbett's skull had been so badly shattered that a pathologist could not accurately count the number of blows.
The Irish businessman's life insurance policy had recently been changed to ensure Ms Martens was the only beneficiary to the exclusion of his two children.