Hello,
A second misconfiguration has left haskell.org with a TLS cert that is about to expire. This will be fixed tomorrow, 7 Feb, between 08:00 and 12:00 UTC. Many small sites are served by the same server. I don’t expect anything more than momentary downtime (if that) for any of them.
I fixed the cert, but there are a few other things I want to take care of during this “downtime window”. I will upgrade the server and make a requested configuration change.
Sorry for not writing the last follow-up – everything went great. 
The maintenance finished within the original time frame.