Normally, a change in a DC (say DC1) is notified to its replication partner(say DC2) after 15 seconds. Once the change is notified, DC2 makes the change in its database. DC2 then notifies its replication partner after ANOTHER 15 seconds. If it's a multi-site setup, the 15 seconds delay WOULD cost a big delay for the FINAL recipient DC. Suppose if the change was an 'Account Lock Out', this big delay will be a pain. Here comes Urgent notification. Urgent notification bypasses the change notification delay and processes the change immediately across all DCs.

Normally, a change in a DC (say DC1) is notified to its replication partner(say DC2) after 15 seconds. Once the change is notified, DC2 makes the change in its database. DC2 then notifies its replication partner after another 15 seconds. If it's a multi-site setup, the 15 seconds delay would cost a big delay for the final recipient DC. Suppose if the change was an 'Account Lock Out', this big delay will be a pain. Here comes Urgent notification. Urgent notification bypasses the change notification delay and processes the change immediately across all DCs.