Reference: SOA serial numbers limitation - BlueCat Address Manager - 9.2.0

• The Data Checker doesn't validate the SOA serial number format.
• The SOA serial number can't be retrieved from secondary DNS/DHCP Servers.
• When resetting an SOA serial number, no other changes are permitted on the zone.
• If the serial number is at the largest allowed value of 4,294,967,295, making a change to the zone resets the number to 1.
• If a zone has been defined in Address Manager but not yet deployed, the Retrieve button returns 4,294,967,295 by default.