To be clear, the challenge types in question where removed from Let's Encrypt production config during the private beta period (when we had a strict whitelist of domains allowed to be issued for), had mitigations for them in while they were out, and we deleted the code for them entirely the other day (in
<a href="https://github.com/letsencrypt/boulder/pull/1247" rel="nofollow">https://github.com/letsencrypt/boulder/pull/1247</a> )