Issued December 9, 2016
A relatively brief order that appears to be an updating of the order of succession. The original order included a listing of eight positions in the succession. This new order lists eighteen positions with a few rearranged.
Not knowing more detail, I am not sure what this might mean given the context of the incoming administration, but at the very least, this is a more clear, deeper list in case of death of the Secretary of Homeland Security.