No way to change TLS cert
The only way to add a TLS cert to a project page is when the page is created. Let's Encrypt will only issue a cert when the page is already up. A Let's Encrypt cert is only good for 90 days. So I will be doing a lot of deleting/adding the same page, and then adding any customizaations I have made to the page settings.
It should not be hard to add a feature to just upload a new key pair to a running page.