Comment 3 for bug 1533631

Looking at the files related to dhclient managed by Network Manager under /var/lib/NetworkManager/ I noticed that although the new lease file seems to contain the correct (in the future) timestamps the "timestamps" file entry for that same lease UUID is still set to the time the original lease expired.

$ ll dhclient6-0775a2a6-a4a1-40bf-bd85-9c3068582dbc-wlp3s0.lease
 -rw-r--r-- 1 root root 1056 Mar 22 16:06 dhclient6-0775a2a6-a4a1-40bf-bd85-9c3068582dbc-wlp3s0.lease

$ cat dhclient6-0775a2a6-a4a1-40bf-bd85-9c3068582dbc-wlp3s0.lease
default-duid "\000\004\301\253\223\321\035\340@\022e\036\025M97\347\361";
lease6 {
  interface "wlp3s0";
  ia-na 3b:bd:74:85 {
    starts 1456324435;
    renew 43200;
    rebind 69120;
    iaaddr 2a02:8011:2007::2 {
      starts 1456324435;
      preferred-life 86400;
      max-life 86400;
    }
  }
  option dhcp6.client-id 0:4:c1:ab:93:d1:1d:e0:40:12:65:1e:15:4d:39:37:e7:f1;
  option dhcp6.server-id 0:3:0:1:ec:43:f6:46:c0:80;
  option dhcp6.name-servers 2a02:8010:1:0:212:23:3:100;
  option dhcp6.unknown-16 0:0:d:e9:0:c:64:73:6c:66:6f:72:75:6d:2e:6f:72:67;
}
$ date +%F-%T --date='@1456324435'
2016-02-24-14:33:55

$ date +%F-%T
2016-03-22-17:28:20

So the lease "starts" time is a month ago even though the lease file update time is the time the address was depreferred.

The "timestamps" file entry for that UUID is:

$ grep 0775a2a6-a4a1-40bf-bd85-9c3068582dbc timestamps
0775a2a6-a4a1-40bf-bd85-9c3068582dbc=1458662760

$ date +%F-%T --date='@1458662760'
2016-03-22-16:06:00

This is the time of the deprefer; presumably set when the lease was originally issued.