systemd uses timeX.google.com as default time servers and this appears to have not been changed by Solus. Upstream was asked by Google to stop using timeX.google.com as their default time servers. However, the servers were left as a default, and only a configure-time warning was added. These servers use a non-standard concept of time and are only intended for use in Google's data centers, not by the public.
It would probably be a good idea to default to a NTP vendor pool instead.