This bug was fixed in the package isc-dhcp - 4.3.3-5ubuntu12.4
--------------- isc-dhcp (4.3.3-5ubuntu12.4) xenial; urgency=medium
* ipv6: wait for duplicate address detection to finish (LP: #1633479).
-- Scott Moser <email address hidden> Mon, 31 Oct 2016 14:32:14 -0400
This bug was fixed in the package isc-dhcp - 4.3.3-5ubuntu12.4
---------------
isc-dhcp (4.3.3-5ubuntu12.4) xenial; urgency=medium
* ipv6: wait for duplicate address detection to finish (LP: #1633479).
-- Scott Moser <email address hidden> Mon, 31 Oct 2016 14:32:14 -0400