Cho, the daughter of Korean Air's chairman, was sentenced to a year in jail
On Friday, Seoul's High Court reduced the sentence to 10 months -- and then released her on two years' probation.
If she runs afoul of the probation restrictions at any point in the next two years, she'll be back in jail, the court ruled.
Prosecutors have a week to decide whether to appeal the new verdict.
Cho was working for Korean Air on December 5 when, as a first-class passenger on an international flight, an attendant served her macadamia nuts in a bag. Cho wanted them on a plate and demanded the plane go back to the gate at New York's JFK airport so a crew member could be kicked off the flight.
When she was originally sentenced in February
, a South Korean judge said her actions threatened the development of the aviation industry and inconvenienced passengers, and ruled that she violated aviation law, changed a flight path and interfered with operations.
On Friday, the court ruled that while she violated safety rules by demanding the plane return to the gate, she didn't cause a change in the flight path.
The flight arrived 11 minutes behind schedule.
When the February verdict
came down, some saw it as an extreme reaction to someone freaking out over nuts. But the flight attendant testified that she was pressured by another Korean Air manager to keep quiet about Cho's behavior. Prosecutors said during her trial that there was a systematic attempt to cover up the incident.
At the time, the judge blasted Cho for her conduct, saying she had used the plane as if it were her personal car and that as a passenger, she could not override crew members and give orders during a flight.
The case, dubbed "nut rage," gripped South Korea, especially because Cho is the Korean Air chairman's daughter.
There is growing resentment over the perceived privileges and nepotism for the families that control the country's top companies.
Cho resigned as vice president at the company a few days after the incident and publicly apologized, saying she accepted "full responsibility."
"I don't know how to find forgiveness," she said.
Park Chang-jin, the chief steward who was booted from the flight, has said the former executive treated crew members like "feudal slaves."
Cover-up of nuts scandal
Park and Kim Do Hee, the flight attendant who served the nuts, had knelt in front of Cho in apology. Kim testified that Cho berated them about the service, and later shoved and cursed her.
When the flight arrived in Korea, the flight attendant said another airline manager, Yeo Woon-jin, pressured her not to talk to investigators about Cho's physical abuse of her and Park.
Airline chairman says he's sorry
After public fury over the December incident, Korean Air chairman Cho Yang-ho apologized to the flight attendants and the public.
Asked in court in January if he knew that his daughter mistreated employees, he said, "I just heard that she's strict with her workers."