"In part this reflects the length of the trial but also the court's capacity. We share this courtroom with the Rotorua District Court ... Rotorua is a busy court."
He said he encouraged "decision makers" to consider this issue and act quickly.
Justice Downs also granted lawyer Vishnu Seger, who is representing the Serious Fraud Office, an extension to file evidence, stating formal written statements must be served by March 8, 2019.
Seger said 60 to 80 witnesses could be called over the course of the trial.
The Serious Fraud Office alleges Grant used her position in several organisations to fraudulently obtain funding from the tertiary education provider Te Whare Wānanga o Awanuiārangi and the Tertiary Education Commission.
Grant, 60, has a background in education, particularly in Māori performing arts in and around the Te Arawa region.
Grant held numerous prominent positions with charitable organisations and in the education sector generally between 2010 and 2014.
The charges before the court relate to when Grant was a trustee of the Te Arawa Kapa Charitable Trust, a member of the board of trustees for the New Zealand Warriors Foundation, as well as the executive director of a private training establishment, Manaakitanga Aotearoa Trust.
Grant's case will be back before the courts for a callover on April 12, 2019. Her appearance has been excused.