The Westchester County District Attorney's office said Tuesday the hearing, originally scheduled for Aug. 14, was pushed back at Kennedy's request due to scheduling conflicts.
Kennedy, 52, a mother of three who is the ex-wife of Gov. Andrew Cuomo and the daughter of the late Sen. Robert Kennedy, pleaded not guilty July 17 in North Castle Town Court to the misdemeanor charge of driving while ability impaired by drugs.
Her lawyer, John Pappalardo, did not immediately return calls seeking comment.
Kennedy denied after the July 17 hearing that the powerful prescription sleep aid was the cause of her crash, saying a battery of neurological tests had revealed she suffered a "complex partial seizure" which caused her to sideswipe a tractor trailer driven by a LaGrange trucker about 8 a.m.
"I remember getting on the highway and then I have no memory until I was stopped at a traffic light and a police officer was at my car door," she said outside the courthouse. "In my discussion with the police officer, I was confused and erratic."
She admitted to police, however, after the crash that she might have accidentally taken an Ambien pill instead of her daily dose of Synthroid, a medication prescribed to treat a thyroid condition. Police found her by the side of the road on Route 22 near Exit 3 after she was reported slumped over the wheel of her damaged Lexus SUV.
State Police brought her to Northern Westchester Hospital, where blood was drawn and analyzed by technicians with the Westchester Department of Laboratories and Research. It revealed the presence of zolpidem, the generic name for Ambien, in her blood five hours after the crash. The drug is usually eliminated within 5 1/2 to eight hours after ingestion, experts said.
Last Wednesday, Newsday first reported that blood tests had found the drug in her system. The Westchester district attorney's office later filed the toxicology report in North Castle Town Court.
After the results became public, Kennedy apologized for the incident.
"I am deeply sorry to all those I endangered that day, and am enormously grateful for the support I have received over the past two weeks," she said in a statement released through a spokesman.
The truck driver she hit, Rocco Scuiletti, 47, was ticketed for leaving the scene of an accident without reporting. He is due in court Aug. 7.