Lohan, 24, has been ordered by Judge Marsha Revel this week to report directly to a rehab facility after being released from jail, which is expected to occur as early as Sunday, a source close to the case tells PEOPLE.
"Lindsay's going to rehab directly from jail, she's been ordered to report there immediately," says the source.
The facility reportedly approved by the judge for Lohan's treatment is Morningside Recovery in Newport Beach, Calif. A rep for the recovery center could not confirm or deny whether Lohan is slated to be admitted there.
Lohan must complete a three-month stay at the facility and won't be allowed to come and go as she pleases.
At an earlier hearing, Judge Revel had ordered the actress to report to rehab within 48 hours of her release from jail, then changed the order to 24 hours, and now wants Lohan to report there directly.
"In all likelihood, the judge is first and foremost concerned about the possibly of a relapse," says Los Angeles-based criminal defense attorney Steve Sitkoff, who's handled more than 100 similar cases, but isn't involved in Lohan's case. "The temptations for a newly released inmate are far too great. And given Lindsay's track record, it seems the judge wants to remind her who's in charge."
Lohan has been serving a 90-day sentence in a solitary cell at the Century Regional Detention Facility in Lynwood, Calif. since July 20 for violating probation in her DUI case.
She's expected to be released from jail early due to overcrowding and for good behavior.