Earlier quoted context omitted.
Any luck this time around? If not I'd give them a telephone call.
I got a copypasta response from them, outlining the steps I already took on their website. Will read it carefully to see if contains any of the info I actually asked for. One thing is that they expect me to use their web interface to file "prior notice" for every single package I send. I see writing a scraping script in my future..
Government loves bureaucracy.