Thanks to all those who made suggestions on how to deal with this issue. I
have a few things to report which perhaps some of you will find interesting.

First, we have 3 major (and a couple of minor) mobile service providers in
Taiwan: Chunghwa Telecom (which also provides fixed line), Taiwan Mobile (I
use it for my phone), and FarEasTone. The problem with accessing devuan.org
was exclusively on Chunghwa Telecom - the other two ISPs worked fine.

I had friends test Chunghwa Telecom on their mobile phones, and it was the
same - devuan.org was blocked. Ditto for their ADSL service.

I went to Chunghwa Telecom to complain - they denied there was any problem
on their end, and that it "must" be my computer that is at fault.

This problem has been going on for four days, and then suddenly about an
hour ago, it magically resolved itself. I can access devuan.org just fine
now.

A great mystery to me, but it is what it is. Anyway, now it works, at least
until it doesn't. If I was really paranoid, I'd suspect that Lennart and
friends put a bomb in systemd's unfathomable spaghetti code to block
devuan.org as soon as there was a beta announcement, but since no one else
on this list encountered that problem, I guess it's all just a coincidence.

cheers,
Robert