sysupgrade can't reach nycdn.netbsd.org

[Ted Spradley <tsprad%talent-free-studios.com@localhost>]

I have an OrangePi 5+ running 11.0_RC5 and I'm trying to upgrade to the
latest 11.0 but sysupgrade can't seem to connect to nycdn.netbsd.org:

sysupgrade: I: Downloading
https://nycdn.netbsd.org/pub/NetBSD-daily/netbsd-11/latest/evbarm-aarch64/binary/sets/base.tar.xz
into /var/cache/sysupgrade
ftp: Can't connect to `2a04:4e42:1b::262:443': Operation timed out
 ftp: Can't connect to `nycdn.netbsd.org:https' 
sysupgrade: E: Failed to fetch
https://nycdn.netbsd.org/pub/NetBSD-daily/netbsd-11/latest/evbarm-aarch64/binary/sets/base.tar.xz

but I can copy and paste that URL into firefox on the same machine and
it works fine. Is there something wrong with IPv6 on my system or is
Firefox using IPv4 or am I just doing something stupid?

-- 
Ted Spradley <tsprad%talent-free-studios.com@localhost>