| Christopher Roderick John Goscomb | Director | 12 Aug 2011 | 31 Dec 2013 | British | 74 years |
| David Anthony Isaacs | Director | 5 Sept 2016 | 31 May 2024 | British | 57 years |
| Dean Leslie Webster | Director | 21 May 2014 | 3 Oct 2014 | British | 67 years |
| Derek Ronald Pitcher | Director | 9 Oct 2014 | 3 Nov 2015 | British | 67 years |
| Douglas Alexander Drysdale Mccormick | Director | 30 Nov 2015 | 6 Sept 2016 | British | 64 years |
| Louise Susanne Cooke | Director | 5 Sept 2016 | 30 Mar 2020 | British | 63 years |
| Patrick Malcolm Mann Sinclair | Director | 1 Jan 2014 | 6 Sept 2016 | British | 51 years |
| Sandra Hogg | Director | 30 Mar 2020 | 1 Jul 2024 | British | 49 years |