The inquiry into David Harold Eastman's murder conviction will start in November.
Acting Justice Kevin Duggan was forced to abandon plans to begin the broad-ranging inquiry in August due to issues with Eastman’s legal representation and a challenge to have the probe’s head sacked.
The judge instead told lawyers involved to be ready by November 5 during an ACT Supreme Court directions hearing on Tuesday.
The extension would allow Eastman’s new senior counsel, Paul Willee QC, hired last Thursday, to read the large amount of material collected.
The present inquiry was ordered in August last year after fresh evidence cast doubt on Eastman's guilt.
Eastman is serving a life sentence for the 1989 shooting murder of Australian Federal Police assistant commissioner Colin Winchester.
He has always maintained his innocence.
The probe's task is to investigate the 1995 conviction on 19 grounds, including fitness to plead, forensic evidence, and the conduct of the prosecution and investigating police.