The charity, which provides employment for disabled and disadvantaged people, had more than 600 contracts, many with the Department for Work and Pensions. Its income had grown from £45m to £70m over four years.
But since July, the trust's external successes have been overshadowed by internal developments. Ian Charlesworth, its chief executive, was dismissed after a disagreement with trustees over plans to expand into Australia and filed grievances against director general Tim Pape and chair John Briffitt. The Charity Commission is having meetings with the trust about its governance.
Last month, the Australian expansion plans that caused Charlesworth's departure were put on hold. Shortly afterwards, Julie Currin, chief finance officer, also left. Her leaving letter to the finance directorate said she was "sad to have reached this decision" but that "recent changes to the trust's leadership have affected me".
Rowena Hayward, an organisation officer for the trade union GMB, said she was concerned about the impact of the changes on staff. "Some are worried about the repercussions of speaking out," she said.
A well-placed source said this week that staff were doubtful about the willingness of Briffitt and Pape to listen. There was particular concern, according to the source, that news of a recent managerial restructure had been circulated for information only and was not put out for consultation.
The trust has said little about recent developments, but last week it hired PR firm Mason Media, which specialises in reputation and crisis management.
It said the charity "absolutely rejects the notion that the organisation may have lost its focus" and "strongly disagrees with the suggestion that senior management has been unwilling to engage in a dialogue with staff".
It added: "The executive team has always had a strong, positive and open communication with staff.
"It is very much a case of business as usual, with director general Tim Pape concentrating on driving the organisation forward in much the same hands-on fashion as he has done since it was founded in 1982."