Norid is upgrading the registry platform from 23 through 25 April this year, causing all registry services to be unavailable during the time period. The services are shut down at 4 PM Friday 23 April.
After the upgrade all registry services will be announced with two sets of IP addresses in DNS. The adress blocks used remain the same as before.
IPv4:
78.91.120.160/28
158.39.52.160/28
IPv6:
2001:700:4600:5::/64
2001:700:4601:5::/64
The name services (DNS) will not be affected.