Calling them ADs is not a good idea because AD is a legal document and
procedure which is not available to us. We should call them something
different. For example, in the Light Sport industry, service bulletins are
issued by the manufacturer because only the FAA can issue an AD.
Lets avoid the confusion as AD carries a legal requirement connotation.
Even service bulletin carries a predefined meaning, but I think we could use
that term since the manufacturer no longer exists.