Pprune, the pp presentation that was leaked to the media pretty much said that the main problem was reduced OCU capacity due to Ops, external tasking and training non U.K. aircrew. It had some stats showing the reduction in OCU demand / capacity all of which were bad but the Chinook OCU was worst. I understand that the Typhoon OCU has pretty much stopped ab-initio training. Hawk engine problem doesn’t help either.