I know as much as is on their website, which isn't much - and a colleague (boffin, Scottish, rotary background, you can probably guess who I mean) has indicated that the design is mostly conducted by somebody ex-army with a limited academic-engineering and flight mechanics background.
Bulldog Aircraft from BJJR seeing is believing
This photograph I took at Telford gives you an idea of the rudder, controls and cockpits...
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