Xenial by default rejects our repo due to non-UTC timestamp on our repo. (similar to https://groups.google.com/forum/#!topic/foreman-users/F2Fvy6YPNkw)
Issue is fixed in a forked version of freight: https://github.com/freight-team/freight/releases
I downloaded each repo from 2.8 -> 4.0 and recreated them using UTC as the Valid-Until and sync'd them back. I'll update Chef to update the "apt.sh" shipped with freight to set the correct timezone.
Here's what I'm applying:
The mentioned fix has been pushed to all of our build agents and I have verified the changes on bamboo-agent09's disk.