We'll have to wait until the investigation results are out but the things that usually kill experienced pilots is the simple stuff such as a stall and spin-in close to the ground.
Hopefully there will be some GPS traces to help investigators figure out what went wrong.

Does the ASH-25 EB28 have the same limitation as the Nimbus 4's where you can exceed VNE or overstress the airframe if you try to recover from a vertical nose down attitude?