Another interesting point is that mixed heli and fixed wing is forbidden in the yellow zone (permanently), and ADSB mandatory in the red zone. With routes 4 and 6 cut.
another item in the testimony was that generally 100% army helicopters flew there with ADSB set to OFF.
and that the accident heli might have put their ADSB to ON, but that the FAA had not received ADSB data from this heli in 730 days.
on ADSB there also was a difference between the Mike and Lima models,
NTSB chair indicated there was a lot more factual information. I wonder if the pull from Congress will lead to a change in the normal process, and release more factual information (with an appropriate disclaimer).