Maxine Carr has been released on probation after serving half of her three-and-a-half year sentence.
Papers relating to Carr's release were found on Hampstead Heath
Carr, 27, was jailed for conspiring to pervert the course of justice with her ex-fiancÚ, Soham killer Ian Huntley.
The media is expected to go to the High Court on Friday to challenge an interim court injunction protecting her identity and release details.
The Home Office said it supported the court order because of "concerns over her health and threats to her safety".
Carr will now be supervised by the National Probation Service to ensure she adheres to the conditions of her release.
A breach of any conditions could see Carr returned to prison.
The court order, requested by Carr's lawyers, bans publication of any information which could lead to Carr's proposed new identity or address being revealed, BBC home affairs correspondent Danny Shaw said.
It also prevents reporting on the care or treatment of Carr once she is freed, including details of a psychiatrist's report, he said.
"Lawyers for the press are likely to argue at a hearing on Friday afternoon that it's too restrictive and should be overturned," he added.
Media lawyer Mark Stephens said: "It is a robust order, possibly the most robust order that we have seen."
He said recent pictures in newspapers showing Carr "looking smug" had heightened uneasiness among the authorities about her release.
"One understands why the court would err on the side of caution during this hiatus and have her identity protected," said Mr Stephens.
Meanwhile, the Home Office says a "thorough" investigation will be carried out into the theft on Tuesday of key documents relating to Carr's release.
It will be led by the director general of the Probation Service, Steve Murphy, and should be completed within a "short period", the Home Office said.
The documents were stolen from a Home Office official's car parked in Hampstead, north London.
The papers containing details of her release were later recovered on London's Hampstead Heath.
Prisons' chief Martin Narey insisted Carr's release plans had not been compromised.
The Home Office had gone to great lengths to keep the arrangements secret.
Carr had been moved from Foston Hall Prison near Derby to a secure location ahead of release.
Carr, 27, was sentenced to three-and-a-half years in jail last December. She has spent 21 months in custody, 16 of which were on remand.
She is also subject to a three-year community rehabilitation order after earlier this week pleading guilty to 20 charges of benefit fraud and lying on job applications.