Seamus Daly, 44, is originally from Culloville, County Monaghan, but now has an address at Kilnasaggart Road in Jonesborough, County Armagh.
He appeared at Omagh Magistrates' Court via video-link.
Mr Daly was one of four men ordered to pay more than Â£1.5m in damages to the families of those killed in the Real IRA attack in August 1998.
He was one of five men named in a BBC Panorama programme, Who Bombed Omagh, in October 2000, that investigated the attack.
No-one has ever been convicted of carrying out the bombing in a criminal court.
Mr Daly has been in custody since April 2014.
A prosecution barrister told the court a substantial amount of evidence relating to mobile phones has been requested from the authorities in the Republic of Ireland, and should be available in six weeks.
What was described as "other more complex material" were subject to legal issues that could take a further four months to resolve.
A defence lawyer said the prosecution had no new evidence since 1999 and his client had been living openly in Jonesborough at all times yet now faced "the biggest murder trial in British criminal history".
The judge remanded Mr Daly into continuing custody until 10 March for a further update on progress in the case.
Relatives of four of the victims of the Omagh bombing were in the court for the hearing.
The man accused of murdering 29 people in the 1998 Omagh bomb will be prosecuted, a court has been told.