OK so the NUS chief exec has just left to go to a comparatively obscure small charity (starting in October) but the ‘succession plan’ is still being worked out for his replacement at NUS? 
www.thirdsector.co.uk/simon-blake-leave-nus-mental-health-organisation/management/article/1489995
Simon Blake is to leave the National Union of Students to become chief executive of Mental Health First Aid England, it has announced.
Blake, who has been chief executive of the NUS for three years, will take up his new role at the community interest company that trains people to help those around them manage their mental health on 3 October.
Our challenge at MHFA England is to achieve parity with physical first aid and the proposed legislative changes we are campaigning for will go a long way to enabling this to happen
Blake said leading the NUS "isn't always straightforward" but he had had a great time working with three different presidents.
He said he would leave this month and have a holiday before starting his new role.
Peter Robertson, his deputy, will take charge until the NUS decides on a succession plan.
MHFA England, which was set-up as a community interest company in 2009, aims to train one in 10 people in mental health first aid.
It is based in London, employs about 60 staff and had income of £2.6m in the 2016/17 financial year.