Counsel assisting Gerard Craddock SC told the court a list of witnesses and issues to be addressed during those hearings would be finalised by Friday.

Despite a decade-long investigation involving hundreds of persons of interest and dozens of searches, no trace of the boy - last seen wearing a Spider-Man suit - has been found.

The inquest into William's disappearance began in March 2019 but was adjourned in October 2020.

No one has been charged in the case and a $1 million reward for information still stands.

In November, 2021 police launched a fresh, month-long search for William's remains that concluded without any obvious breakthroughs.

In May, a review into evidence that the three-year-old's former foster mother might have been involved in his disappearance was suspended after a police request to the NSW Director of Public Prosecutions.

Investigators had provided a brief for prosecutors to consider potential charges against the woman, who cannot be named for legal reasons, who they believed might have disposed of William's body after his accidental death.

The foster mother has always denied having anything to do with William's disappearance.

In March, both of William's former foster parents were found guilty of intimidation charges in relation to another child who was also previously in their care.

Arguments over household chores, including cleaning a bedroom and stacking the dishwasher, formed part of the prosecution's case against the pair.

A magistrate dismissed a slew of other domestic violence allegations facing the couple, with the former foster mother cleared of five counts of intimidation, while the foster father had one count of assaulting the child dismissed.

Prosecutors relied on more than 1000 hours of covert recordings made in the couple's home and vehicles over 14 months in 2020 and 2021 by detectives investigating William's disappearance.