That could mean many things — including days in court this summer, in the orbit of the election campaign in the fall, or even an extension of the case into 2016.
The longer the trial goes, the better the chance that the details of the Auditor General's forensic audit of all senators, due in June, could be referenced in court.
The suspended senator and former Conservative faces 31 counts of fraud, breach of trust and bribery, all related to expenses and contracts he signed.
Ontario court Justice Charles Vaillancourt finally said Wednesday what many in the courtroom had been guessing about since last week.
"I don't see us completing our task in the assigned number of days," Vaillancourt said.
The trial was originally scheduled to run until June 19, with a break from May 13 to May 31 while one of the Crown prosecutors deals with pre-trial responsibilities in another case.
But seven days into the process, only two witnesses have taken the stand, even though dozens are expected to testify.
Defence lawyer Donald Bayne is going deep into the Senate's often broad rules and procedures with each witness, trying to demonstrate his client operated within the lines. The Crown has had about three hours of questions through the entire stretch.
The likelihood of more days simply getting tacked on in June and July is unclear. All players in the trial must look at their timetables, and there must be room available in the Ottawa courthouse.
There are more challenges when looking at the fall schedule. Crown Prosecutor Mark Holmes is booked to work a murder trial. October is the time foreseen for the trial of former Liberal senator Mac Harb, who is also facing charges of fraud and breach of trust in relation to his living expenses.
Outside the courthouse, the Toronto-based Vaillancourt told reporters the Duffy case is a priority.
"They can always rearrange my schedule in Toronto and then I'll come up here and deal with the case here," he said. Vaillancourt said he couldn't speculate on whether the case would run into the election period this fall, or into 2016.
"I don't know how long it's going to take, because I don't control the number of witnesses, or how long it takes with each witness. So we'll just have to wait and see," he said.
On Wednesday, Bayne continued a second day of cross-examination of Senate human resources officer Sonia Makhlouf.
A set of charges that Duffy faces relate to $65,000 in contracts awarded to friend Gerald Donohue's company. Some of that money subsequently filtered down to other service providers, including an office volunteer, a makeup artist, and a photo developing shop.
Bayne pointedly went through some of these examples with Makhlouf, arguing that while Duffy probably should have used a different procedure to cover the photo service costs, that doesn't mean they weren't legitimate expenses.
Likewise for the $500 paid to office volunteer Ashley Cain, via the Donohue contract.
"It's not a private personal matter, he's not lining his pockets, he's not painting his house, he's trying to run his office and he's got services from a good worker over a four-to-five-month period and that's clearly in relation to his activities in the Senate," said Bayne.
"Yes," said Makhlouf.
All of this meant to support Bayne's contention that Duffy might have made administrative mistakes, but is not guilty of criminal behaviour.
Bayne drew attention to the fact that the contracts in question were put in place before the Senate tightened some of its procurement policies in 2011.
Before then, senators could arrange purchases under $2,500 without a contract. After the changes in 2011, officials said senators could make their own arrangements only "in emergency situations."
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