IPv6 support has recently been completed in Boulder (the LE CA software) already:<p><a href="https:&#x2F;&#x2F;github.com&#x2F;letsencrypt&#x2F;boulder&#x2F;issues&#x2F;593" rel="nofollow">https:&#x2F;&#x2F;github.com&#x2F;letsencrypt&#x2F;boulder&#x2F;issues&#x2F;593</a><p>That was the main blocking issue. IPv6 in LE is coming very soon.