The start date for a long awaited inquest for missing teenager Arlene Arkinson has been "set in stone", a coroner's court has been told.
Even though Brian Sherrard said the case was "on track" to begin on February 1, the coroner warned he would not tolerate any further delay to the long-running case.
He told a preliminary hearing at Laganside Court: "At this stage I am not minded to compromise the date at all."
Arlene, 15, from Castlederg, Co Tyrone, vanished after a night out at a disco across the Irish border in Co Donegal in 1994.
She was last seen with convicted child killer Robert Howard, who died in prison last month.
Howard was acquitted of the teenager's murder by a jury that was unaware of his previous conviction for murdering a schoolgirl in south London.
The 71-year-old always remained the police's primary suspect in Arlene's disappearance and had been set to give evidence before the inquest.
In eight years of preliminary proceedings the number of scheduled start dates have been missed because of police delays in disclosing documents and issues around security vetting.
A large number of files have now been handed over to lawyers for the Arkinson family and more are due to be disclosed on Tuesday.
However, there have been problems with pagination and indexing, the court heard.
Kevin Rooney QC, barrister for the PSNI, said he did not anticipate any re-call of the documents.
He said: "We feel that is something that can be resolved in due course.
Mr Rooney said a number of outstanding documents were not "fundamental" to the case.
"They (police) are working extremely hard trying to get this done," he added. "They were in over the weekend again.
"Depending on whether there is a serious crime incident, which I hope there isn't, or if there is a serious crime trial, which there was last week, they are working hard on this."
Detective Superintendent Karen Baxter told a previous court hearing that the Police Service of Northern Ireland had diverted more than 2,500 hours, at a cost of almost £75,000, to the case since April.
The coroner set a deadline of November 30 for all information to be handed over.
"The date of February 1 is here. It is very important we retain that. Everybody needs to re-double efforts," said Mr Sherrard.
Meanwhile, it also emerged that although the inquest will be held at Laganside court complex in Belfast city centre, proceedings will be streamed to Omagh courthouse via live videolink to facilitate members of the Arkinson family.
The case was adjourned until December 7.
A lawyer for a convicted child killer due to testify at the inquest of a missing schoolgirl has warned of potential legal action if delays disclosing state papers persist.