A multi-day blockade at the world's largest coal port will be shortened if it goes ahead but police still expect civil disobedience if the planned protest proceeds.
Rising Tide organisers said the event from November 22 to 24 would be one of the world's most significant climate protests, involving demonstrators in canoes and kayaks blocking the Port of Newcastle.
But police have asked a court to deem the planned "protestival" - which is also due to feature live music from dozens of acts - an unlawful assembly, rendering anyone who stops port traffic liable to be arrested.
The case returned to the NSW Supreme Court on Tuesday, when the court heard a new application had been submitted for a 30-hour blockade, shorter than the original 50 hours, while also halving the time protesters would be camped in the area to four days.
A 30-hour blockade took place in 2023, but police arrested 109 people after they stayed in the water for longer in a move which attracted global media attention.
The court was previously told the most severe penalty was a $400 fine and the majority were not prosecuted.
NSW Police Assistant Commissioner David Waddell said his concerns remained despite the shorter duration.
He did not think protesters would follow directions if the court prohibited the protest and police would need to arrest those who paddled out.
"It's clear that their intent is to enter the water and we saw that last year ... it has clearly been stated by members of Rising Tide that they intend to engage in civil disobedience," Mr Waddell said.
Justice Desmond Fagan earlier questioned why protesters were fighting against the protest being declared unlawful.
"Why do you resist the order for prohibition if what is intended is that protesters will really only gain amplification for their cause ... by not complying with the law?" he asked.
Rising Tide barrister Amanda Sapienza said not everyone was trying to get arrested.
"That's not the intention of all the organisers, the media attention that comes from the arrests is not the only point of the assembly," she said.
Briohny Coglin, a lawyer who filed the protest forms, disagreed people were being encouraged to get arrested.
She said Rising Tide's objective was to draw attention to governments continuing to approve new coal and gas projects, and organisers would instruct participants to follow directions and co-operate with police.
Those remaining in the water when the protest period expired would be warned.
The group is calling for immediate cancellation of new fossil fuel projects, higher taxes on exports and an end to coal shipments from Newcastle by 2030.
The case returns to court on Wednesday.
Premier Chris Minns said the protest had been opposed because it was dangerous and would impact the economy, suggesting further government action could follow to protect coal infrastructure.
"I think the government's going to have to make some decisions in the next few weeks about protecting that coal line and ensuring the economy doesn't close down as a result of this protest activity," he said.
