De Rosa joined the squad this year and was appointed to Race Engineer duties on the #23 PremiAir Camaro, marking a reunion with Tim Slade after two years together at the Blanchard Racing Team.

Speedcafe understands that he has chosen to step away from the team, while Data Engineer Julia McGarry has also left.

She had joined PremiAir at last year’s Boost Mobile Gold Coast 500, immediately after exiting Team 18 in the wake of its bungled fuel calls at the Bathurst 1000.

“While very thankful for his service to date, having Mirko De Rosa located in Melbourne while working as the lead engineer for the #23 PremiAir Nulon Racing Camaro has not worked out as the team and Mirko had hoped, and so the decision has been made that Mirko will step back from the role, with Ludo Lacroix taking up the role of lead engineer for Tim Slade moving forward while continuing his over-arching role as Competition Director for PremiAir Nulon Racing,” read a statement from the team.

“The team thanks Julia McGarry for her service but the decision has been made that a more senior Data Engineer is required in this position and details of the new appointment will be made in the coming weeks.”

Slade is currently 21st in the drivers’ championship after a tough season-opening weekend at Mount Panorama, something of a bounceback at Albert Park which saw him finish top 10 in three races out of four, and then the disappointment of a start crash at Taupo while trying to pass pole-sitter Cam Waters on the run to the first corner of the wet Saturday race.

Team-mate James Golding is currently 10th in the drivers’ championship.