Their website
https://www.dynamiq-eng.co.uk/ is nerd heaven. Seems like they've been at the bleeding edge of engineering consulting for over a decade and have provided quite a variety of customer solutions over that time.
Dig deeper in that website and there's an announcement that they're designing their own sub 500kw gas turbine engine. There's also an innovative centrifugal compressor fan design although I'm not sure if it's related.
As for the secret helicopter, I just hope it's sporty enough in its handling rather than something boring made to ferry golfers and their golf clubs.