When using your own custom domain and an SSL Certificate (Let's Encrypt or 3rd Party), you should be able to update the Traffic encryption settings to "Always use https://" on that custom domain name. It defeats the purpose of even securing the site if a visitor has to manually type in "https://", when we're trying to gain the trust of a potential new member's information being safe when the browser they're using is telling them the site is "Not Secure". For this to be a paid hosting service and only allowing to use a "wildapricot" subdomain if you want https:// to load by default is unacceptable.