It's some feud between the 1.1.1.1 operators and the archive.is operator. I never really cared enough to figure out who was at fault. Probably both of them.

edit; here you go: https://jarv.is/notes/cloudflare-dns-archive-is-blocked/

Here are a couple more mirrors:

https://webcache.googleusercontent.com/search?q=cache:http%3...

http://cc.bingj.com/cache.aspx?q=url:http%3A%2F%2Fkcall.co.u...

Hopefully one of them will work for you.

Those will stop working some time soon. Long-term mirror: https://web.archive.org/web/20200115163630/http://kcall.co.u...

Do you have AT&T? Check this out: https://www.google.com/search?q=At%26t+1.1.1.1+blocking

It's quite the other way around.