I'm getting the message:
'Maintenance mode
7/31/18
Sorry for the inconvenience.
Our website is currently undergoing scheduled maintenance.'
Their Facebook page says 'Good morning!!
The site will be down most of today to migrate to a new host (yes, again). I'm sorry for the inconvenience. This new host has a really good reputation so I'm confident we're not going to have any more issues.'
Maybe the 'issues' they refer to have given Avast a problem, although Avira is fine with the site.