| Andrea Alessandro Orlandi | Director | 13 Nov 2014 | 29 Apr 2016 | Italian | 55 years |
| Andrea Alessandro Orlandi | Director | 26 Jul 2022 | 29 Jun 2023 | British | 55 years |
| Ben John Tolhurst | Director | 7 Aug 2023 | 31 Oct 2024 | British | 60 years |
| Christopher Mark Taylor | Director | 6 Nov 2014 | 21 Jun 2022 | British | 67 years |
| Christopher Raymond Andrew Darroch | Director | 6 Nov 2014 | 5 May 2023 | British | 60 years |
| David John Price | Director | 23 Jul 2015 | 21 Jun 2022 | British | 66 years |
| Emily Clare Bird | Director | 21 Jun 2022 | 22 May 2025 | British | 45 years |
| Ira Atanasova Panova | Director | 23 Jul 2018 | 1 Oct 2019 | Bulgarian | 42 years |
| Ira Atanasova Panova | Director | 23 Jul 2021 | 21 Jun 2022 | Bulgarian | 42 years |
| Kirsty Ann-marie Wilman | Director | 30 May 2023 | 31 May 2024 | British | 46 years |
| Matthew Hele | Director | 29 Jun 2023 | 24 Apr 2025 | British | 53 years |
| Richa Srivastava | Director | 21 Jun 2022 | 21 May 2024 | Indian | 37 years |
| Richard James Peacock | Director | 21 May 2025 | 2 Jun 2025 | British | 52 years |
| Richard James Thor Kolb | Director | 13 Nov 2014 | 30 Jun 2015 | British | 56 years |
| Roderick Carnan | Director | 27 Apr 2016 | 20 Jul 2022 | British | 70 years |
| Styliani Koukidou | Director | 1 Oct 2019 | 23 Jul 2021 | Greek | 37 years |
| Thomas Oliver Jackson | Director | 23 Jul 2015 | 24 Apr 2025 | British | 45 years |
| Timothy George Barlow | Director | 23 Jul 2015 | 23 Jul 2018 | British | 40 years |