The AAIB report has appeared in Bulletin 3/2017.
https://www.gov.uk/government/upload...ull_3-2017.pdf
scroll down to page 32
The odd thing is, it doesn’t really explain why the aircraft got into an 18º nosedown situation, although it does cover the events leading up to it.
It also says
Without the means of providing significant vertical thrust, the aircraft is not capable of true vertical landings (in calm or very light wind conditions).
Anyway, I gather that’s it for the AAIB’s involvement.