[2] In late 2023, Mackenzie announced he would leave MLav Moto3,[3] and for 2024 is a UK-based motorcycle racing track instructor,[4] rider-assistant to brother Tarran Mackenzie racing in World Superbikes,[5] and social media creator for his team, MIE Honda.

[6] Mackenzie retired from racing at the end of the 2021 British season where he competed in National Superstock 1000, finishing in fifth position.

[9] In a February 2021 Motorcycle News interview, he confirmed that he'd had a bad year and he was reliant upon funding provided through YouTube, Patreon and Amazon when trying to arrange a race machine for 2021.

[10][11] For the first half of the BSB 2018 season, he rode for Moto Rapido Racing Ducati replacing injured John Hopkins.

The team and Mackenzie announced their mutual decision to part company at the Knockhill BSB round practice session on 7 July, due to the rider's poor results.