https://www.ntppool.org/ seems to be down. It returns ‘503 Service Unavailable’. Is this ongoing maintenance, I’m unaware of, or is there more to it? Status for all systems is shown as “operational”.
It’s online again, the stats show it was offline for a few hours and then restored.
Could be a simple IP-change.
No need to panic, unless it happens a lot.
Just a glitch in my book 