ipAddressPrefixAdvPreferredLifetime 1.3.6.1.2.1.4.32.1.8

The remaining length of time, in seconds, that this prefix will continue to be preferred, i.e., time until deprecation. A value of 4,294,967,295 represents infinity. The address generated from a deprecated prefix should no longer be used as a source address in new communications, but packets received on such an interface are processed as expected. The default for IPv4 prefixes is 4,294,967,295 (infinity).