In a report in the Australian Financial Review, PBL chief executive Ian Law dismissed speculation surrounding the project's viability, but admitted the project may fall behind schedule.
"We've been slightly delayed in signing agreements with equipment suppliers, which means the start date might slip from late 2011 into 2012," Law is quoted as saying.
"But we are currently finalising our financing structure and everything is moving ahead."
PMP chief executive Richard Allely claimed last month that he was "relatively confident" that the facility would not go ahead, and that he was "optimistic" PMP would retain PBL as one of its major clients.
This view has gained traction with PMP's transformation plan - which was announced last week - detailing the company's plans to convert its Moorebank site into a facility dedicated to magazine printing, with its Clayton site to focus primarily on catalogue printing.
Law, however, said this would have little bearing on PBL's plans.
"The changes at Moorebank sound like what we're doing, that is, creating a national magazine and distribution operation," he said. "It's a good move for PMP, but our agreement with it has not changed."
PBL has cagey about releasing further details since its initial announcement in October last year, with industry estimates putting the cost of the project at around $160 million.