A "significant" issue has arisen in a delayed judicial challenge to a Police Ombudsman report into the Loughinisland shootings in Northern Ireland, a lawyer said.
Six Catholic men were killed by loyalist paramilitaries as they watched a World Cup football match in a pub in the Co Down village in June 1994, the Ombudsman said.
The victims were watching the fixture between Ireland and Italy when loyalists entered the Heights Bar and opened fire.
The Ombudsman said there had been collusion between some police officers and the gunmen.
Two retired officers are attempting to have the watchdog Dr Michael Maguire's report overturned in a legal challenge at Belfast's High Court.
Judgment was deferred for a week to allow for further legal submissions and former director of public prosecutions (DPP) Barra McGrory QC has been recruited to represent the Ombudsman's office.
Solicitor for the families Niall Murphy said: "The court has provided a short adjournment to permit a significant issue to be explored and we welcome the opportunity to explore that significant issue and will consider our options as information becomes available.
"It is a sensitive issue so that is as far as we are going to take it today."
Last December Mr Justice McCloskey said the Ombudsman's finding on collusion was "unsustainable" but deferred deciding whether to quash the report.
He had been expected to complete his findings on Friday but received a last minute submission from lawyers.
Emma Rogan, whose father Adrian was among those killed, said: "It is a delay, we are frustrated, but we welcome the opportunity that our legal teams are able to explore this development and we see where we go from there.
"We are relieved that it has not been quashed today."
The men who died were Adrian Rogan, 34, Malcolm Jenkinson, 53, Barney Green, 87, Daniel McCreanor, 59, Patrick O'Hare, 35, and Eamon Byrne, 39.
Five others were wounded.
The delay followed a last-minute change in the Ombudsman's counsel and a suggestion by another barrister that individual parts of the report could be quashed.
The matter is due to return to court next Friday.