Vincent Stanford, 25, was listed for arraignment in the Supreme Court in Sydney on Friday, but it is understood the matter was taken out of the list on Thursday afternoon.

The reason for the delay was not immediately available.

Stanford’s twin brother, Marcus, was also listed for arraignment on Friday on a charge of accessory to murder after the fact, but that matter was also stood over.

Both cases are now listed for mention on Tuesday, July 5, at which time it’s possible a new date for arraignment will be set.

Marcus Stanford pleaded guilty to his charge in Griffith Local Court on March 31, but Vincent Stanford has yet to enter a plea.

During a mention of the murder case the same day, Vincent Stanford’s legal team flagged the possibility of a mental health defence.

In May the case was adjourned to Friday after Vincent Stanford's lawyer requested time to consider two reports that he said would have a bearing on how Mr Stanford would plead.

At that time Vincent Stanford appeared by video link in the NSW Supreme Court over last year's alleged rape and murder.

His twin brother also appeared separately by video link.

Ms Scott, an English and drama teacher at Leeton High School, was last seen on Easter Sunday preparing lessons before her planned honeymoon.

Police allege Ms Scott was murdered by Vincent Stanford between 1.40pm and 2pm on April 5.

Her body was found in the Cocoparra National Park on April 10, the day before she was due to be married.

It is understood the Stanford family often travelled to the area for camping trips.

The twins were born in Tasmania and moved to the Netherlands in their teenage years but later returned to Australia.​

In his only court appearance to date Vincent Stanford kept his head bowed during a brief video appearance.

In March this year police alleged the school cleaner sent Ms Scott’s engagement ring to his twin brother in the post, Fairfax Media understands. 

​The police charge sheet says that Marcus Stanford "did assist" his identical twin brother and it is believed he received her engagement ring in the post in South Australia.