Kimi Raikkonen's race engineer David Greenwood has left Ferrari ahead of the 2018 Formula 1 season.
Greenwood joined Ferrari for 2015, having held the role of chief engineer at Marussia, and has spent the last three seasons working with Raikkonen.
He has left the team for personal reasons and will return to the UK, where it is understood he will take up a role on Manor's World Endurance Championship project.
The British team will step up to the privateer LMP1 ranks for the WEC's 2018/19 'superseason' using Ginetta's new prototype.
Ferrari has yet to make a decision on who will replace Greenwood, but one is expected in the coming weeks.
As part of the minor reshuffle, its former pitwall-based operations chief Diego Ioverno will no longer travel to races and will instead work from the factory.
It remains unclear as to whether he will be directly replaced or if his duties will be split between engineering staff at the track.
One option is that Jock Clear takes on some of those duties as part of his role as head of race activities.
Further adjustments to the structure and respective staff duties are expected in the coming weeks ahead of pre-season testing, which starts on 26 February.
Ferrari will unveil its 2018 F1 challenger on February 22 - its new car successfully passed the relevant FIA static and frontal crash tests in December, believed to be the first new model to do so.