Neill-Fraser, 65, is serving 23 years' jail for the 2009 murder of partner Bob Chappell on the couple's yacht in Hobart.

A second appeal against her conviction, launched on the grounds there is fresh and compelling evidence, was set to be heard in March next year.

On Friday, Hobart Supreme Court heard Neill-Fraser's defence barrister, Tom Percy QC, was not available until late May.

Justice Helen Wood said she would try to accommodate the request to push back the hearing and both legal teams would be notified next week.

Neill-Fraser was in 2010 convicted of killing Mr Chappell, 65, whose body has never been found.

She was granted leave to appeal in March under a new Tasmanian law requiring her to provide "fresh and compelling" evidence.

Director of Public Prosecutions Daryl Coates told the court some of the evidence in the appeal documents was inadmissible opinion or "just completely irrelevant".

In previously submitted court papers, Neill-Fraser's legal team argues there is fresh evidence that proves then-homeless teenager Meaghan Vass was aboard the yacht the night of Mr Chappell's murder.

The DNA of Ms Vass was found on the boat.

Neill-Fraser has maintained her innocence and outside court her daughter Sarah Bowles expressed frustration at the drawn-out legal process.

"It's an extremely emotional and sad time for us. My kids really miss her," she said.

"This is time we're never going to get back."

Neill-Fraser's lawyer Paul Gallbally said both legal teams would meet in January to decide what evidence would be put before the court.

Justice Wood told the court the hearing could run for more than two weeks.

Another directions hearing is expected in February.

Neill-Fraser's first appeal was in 2012 dismissed by the Court of Criminal Appeal.

Australian Associated Press