Please add a httpS setting to the Hub so that all access uses the correct protocol.
Looking at my access logs it seems the Uptime ping always uses http:// to access our sites, and then after an error 301 (Moved Permanently) it goes to the httpS protocol. I'm not sure but I think this might be responsible for some Uptime down/up notices.
I don't know if this is the best solution but I think a simple checkbox for each site in the Hub would eliminate this one issue, where all queries from the Hub would then use httpS.
Taking this a bit further, when the Hub gets any kind of server error from our sites I think it would be helpful to see that in a log. Consider a single Hub log that includes all errors being returned from any site, with an option to temporarily remove logging for any given site in development where we expect errors. Temporary, because we don't want to accidentally leave such logging off for any site.