The East of England Ambulance Trust has said chair Maria Ball has resigned.
The Trust says its focus is now solely on improving the service to patients and better support our staff.
Vice-chair Paul Remington said: "We are developing a transformational plan, details of which will be published next week. This will involve recruiting many more front line staff, better managing sickness absence, clearer career pathways and a renewed focus on patient handover delays."
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Very cold with snow showers and significant wind chill. Temperatures dropping to -3 deg C (27 F)
Tributes have been paid to a 25-year-old man from Essex who was found dead in a river in "unexplained" circumstances.
Feeling very cold and mostly sunny today with some snow showers overnight. Top temperatures reaching only 2 deg C (36 deg F)