Bug#813108: www.debian.org: udd.debian.org is unreachable

Package: www.debian.org
Severity: important

udd.debian.org is unreachable and with how-can-i-help installed,
this makes upgrades freeze for a few minutes:

how-can-i-help: Error downloading data file: Network is unreachable - connect(2) for "udd.debian.org" port 443

-- System Information:
Debian Release: stretch/sid
  APT prefers unstable-debug
  APT policy: (500, 'unstable-debug'), (500, 'stable-updates'), (500, 'unstable'), (500, 'testing'), (500, 'stable'), (1, 'experimental')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 4.3.0-1-amd64 (SMP w/12 CPU cores)
Locale: LANG=POSIX, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)