The forum was under a big DDoS attack.  theymos has long resisted the idea of protecting the forum with the most cost effective DDoS protection providers like Cloudflare because doing so hands the SSL private keys to a 3rd party company and increases the privacy risk of the users.  Instead he decided to try hosting at another provider with automatic DDoS mitigation where theymos continues to directly control the SSL certificate.  This provider is considerably more expensive than Cloudflare, which he considers necessary to protect the users.  It remains to be seen if their service is reliable and worth the cost.