Hazel Stewart's appeal against her conviction for the murders of her husband and the wife of her ex-lover may not go ahead until September, it has been revealed.
She is to be examined by a psychiatrist and might have to undergo a second test, the High Court in Belfast was told.
Stewart, 48, a mother of two, was convicted at Coleraine Crown Court last March and later jailed for a minimum of 18 years for the murders of Constable Trevor Buchanan, 32, and Lesley Howell, 31, the wife of her then lover, dentist Colin Howell.
Howell gassed the two victims before stage-managing the deaths to make them look like suicides and fool investigating officers.
Police only discovered what really happened when Howell, 52, confessed to the police in January 2009 about what he and his lover got up to in May 1991 when the bodies of Lesley and Constable Buchanan were discovered in a garage in Castlerock, Co Derry.
Howell was later sentenced to a minimum of 21 years, but Stewart is still protesting her innocence. Her second husband, former RUC Chief Superintendent David Stewart sat in the public gallery at the Court of Appeal and heard that his wife's challenge to her conviction may not take place for several months.
The Lord Chief Justice Declan Morgan was told by her lawyer, Mark Reel QC, that it will be March 20 before the report of the first psychiatric examination is ready, and depending on what it contains, there might have to be a second assessment carried out.
The judge asked: "Is there a realistic prospect of this case being heard before the summer?" Mr Reel replied: "It is possible, but I can't put it any higher."
Normally the summer recess takes in the months of July and August and the new term does not begin until early September.
Stewart, from Ballystrone Road, Macosquin, Coleraine, is being held in Hydebank Wood women's jail in south Belfast. At an earlier hearing a judge said there were "insufficient grounds" to grant her leave to seek an appeal.