On Friday, 12th of March at 3:39 am, one of two routers in a redundant pair failed. Partial failover to the backup router took place but due to invalid configuration on the backup router, some redundant gateway (VRRP) interfaces did not come online.
By 4:43 am the problem was identified and a fix to the redundant router configuration was put in place.
Emergency network maintenance was scheduled on Saturday morning to permanently remediate the problem and restore full redundancy. During this maintenance, gateways were moved to a new pair of routers.