Comment 28 for bug 1609898

Unfortunately, while I initially put in the bug description that there was no regresssion potential, I've been made aware that some network configurations rely on the previous (incorrect) behavior of the dhcp client to set a prefix len of /64. Such configurations will break when the dhcp clients are updated, and the dhcp server must be updated to use Router Advertisements to provide the prefix len to dhcp clients. I updated the description's Regressions section with more details.