my EFA seems to accept mail for users, that are not existing on the destination server.
I have "spam not delivered" report activated.
I then get an NDR to postmaster@myefa for that report email.
That's kind of shot in my knee

I bet postfix is the point to look at for this as it seems to have a powerful address verification.
I wonder, why this isn't on by default or am I something missing?
Regards
Akl