Comment by gzread

All of that's a problem with DNS too, even updating the IP. You could still use it to get the initial entry point if you wanted. But when you serve a webpage with an automatically generated pointer to image3.yourdomain, the only reason not to make that an IP is HTTPS, and LE just started issuing IP address certificates. Think about it - it saves a few round trips.

If the IP is anycast, all the better.