Sydney terror plotter's jail term reduced

He had pleaded guilty to conspiring with Sulayman Khalid, a juvenile and others in 2014 to do acts in preparation for a terrorist act to advance violent jihad.

He also admitted four firearm offences.

The NSW Court of Criminal Appeal on Friday reduced his sentence to 16 years and six months, with a non-parole period of 12 years and six months.

Although the Supreme Court judge had sentenced Almaouie in accordance with the applicable law at the time, the DPP accepted that - in light of a subsequent appeal decision - he had erred in his consideration of the plea of guilty.

The appeal court said the concession was well founded and it re-sentenced Almaouie in line with the "Xiao" decision.

Khalid and the juvenile have already had their sentences cut in line with the decision which ruled that the utilitarian value of a plea of guilty should be taken into account in federal offences.

In the agreed facts for the conspiracy, Khalid was described as the "leader" and Almaouie as "high up in the group".

The group's crude plan involved killing police officers, targeting government buildings, sourcing firearms and engaging in guerilla warfare with the help of an army of indigenous people they'd converted to Islam.

In conversations and planning documents, they used code words such as "banana" and "motorbikes" instead of firearms. "Wombat" meant Khalid's garage - their meeting place.

Khalid also made a series of YouTube videos including one where he threatened secret service agencies around the world saying: "It's either you will become a Muslim, and you will believe in Allah, or you will die by the sword."

In re-sentencing Almaouie, the appeal court applied a discount of 10 per cent on account of the utilitarian value of his guilty plea.

It also accepted if it didn't interfere with his sentence, there would be an "unjustified disparity" between his and Khalid's reduced sentence, given Khalid's greater role in the offence.