ExonMobil, which operates Fife Ethylene Plant, said it had stopped using its elevated flare as planned.
Over the next two days, it will complete the remaining stages of the process, but anticipates that any associated flaring should be contained in the ground flares.
In an update to local communities, Martin Burrell plant manager, said: “I do hope that the actions we took in advance, to significantly reduce both the size and duration of the flare, helped to minimise any community
“We thank you for your patience and understanding while we undertake our plant upgrade."
At Fife NGL, which is operated by Shell, refurbishment work is being carried out to the inlet plant from the main pipeline from St. Fergus, and its associated valves.
Some of the work will be provided by around 60 contractors.
The company plans to use its elevated flare for low volumes of ethane until April 15, and then the ground flares between the 15th-18th.
The ground flares are less visible during the day but can cause a glow to be seen locally at night.
Fife NGL plans to reintroduce volumes to the plant on May 6, and use its elevated flare for low volumes of ethane through next month.
The down time is essential so that operators in the North Sea supply system can complete detailed inspections, servicing and upgrades as it invests in maintaining the integrity of operations.