Jetjr,
You'r getting there.
It is the ratbag Australian rules, which means that two functionally identical Jabiru, both "Experimental", both "owner maintained", different only in that one is 19-, the other VH-, are treated differently re. airspace.
There is no shortage of other examples, and NO risk management justification re.the type of aircraft, type of engine or system of maintenance restrictions, that is all straight out prejudice.
As I have said, it dates back to early days of AUF, and has nothing to do with the great god, "Safety", but all that is long lost corporate knowledge in CASA, where the excuse for all inaction, all refusal to change (or the reason for restrictive change) is S.9A of the Act as a crutch.
Tootle pip!!