Folks,
got aware of this today. New law in Austria will effectively ban flights with passengers to that country unless the owner/operator of each individual airframe appoints a fiscal representative to declare and cash in the new national passenger tax.
Legislation here:
Flugabgabegesetz (German)
There is a petition out to counter this and other stuff, see here:
Petition (German)
According to this the new law will become valid after March 31st.
The implications are very serious indeed and would in fact amount to a total ban for foreign GA aircraft unless they are willing to have themselfs pre-registered and represented by an Austrian lawyer.