I'm thinking that if we're able to properly brainstorm effective verbiage for this document request, then that document could flow better into the creation of a "How do I manually install an LE cert for my domain?" document which could be linked to the "No Planned Support" section of the list.
Hosterion - https://hosterion.com - supports Letsencrypt since many years ago. We even wrote our our cPanel plugin to activate and renew LES SSL, before one was available from cPanel.
All web hosting costs benefit from free SSL certificates for all domains hosted. You create your own SSL certificates Let's Encrypt from cPanel, and later on they are renewed automatically, without your intervention. Unlimited web hosting ✔ Hosterion
Let's Encrypt certificate is automatically generated once the domain points to our servers, of course we cannot enforce the redirect, that is the client's responsibility since they create their own websites and configure as they please.
If you're controlling the certificates installation, why not the redirect too? Seems to me you have access to the webserver, at least on shared hosting. For services like VPS I assume you don't get certificates too, so I assume we're talking about shared hosting here to begin with?
Usually the redirect is done at the webserver level using the HTTP Location header, not necessarily the "website" level.