I'm sorry about the downtime, but unfortunately the matter is out of my hands. For some reason after the server upgrade the server has been going up and down repeatedly. Just when I thought everything is normal after two days of uptime the server goes down again. I've filed an emergency support ticket with the host an hour ago, but no fix yet. I know that the host has been under massive DDoS attacks for the last few days (due to another customer), so this might be the reason.