"I have the EC ASB now giving 3 hours between downloads for the EC225."
Whether it is 3, 4 or 5 hours between HUMS downloads, I believe that the specified maximum period will have to include all rotors running time on the ground and helidecks. To the best of my knowledge and belief, the lubrication pumps and the bevel gear on the shaft are incurring the same or similar wear and tear, airborne or not.
This will impose a serious limitation on the radius of action, because non-airborne time accounts for something like 15% to 25% of total running time. Senior Management is aware of this.