The time servers at NIST/Boulder will be down for a software upgrade tomorrow (11 December) starting at about 9 am local time (16 UTC). The upgrade will take a few hours. This includes servers with IP addresses 132.163.96.x except for 132.163.96.1, which will continue to operate. It also includes the internal servers with IP addresses 132.163.4.x.
The server at WWV with address 132.163.97.7 will be down for the upgrade for a short time on Thursday morning, starting at about 10 am local time (17 UTC).