404 on builds.midonet.org

eg.
http://logs.openstack.org/38/460838/3/check/gate-tempest-dsvm-networking-midonet-v2-full-ubuntu-xenial-nv/e89612c/logs/devstacklog.txt.gz

2017-05-24 12:03:02.536 | Reading package lists...
2017-05-24 12:03:02.565 | W: The repository 'http://mirror.kna1.citycloud.openstack.org/ubuntu xenial Release' is not signed.
2017-05-24 12:03:02.565 | W: The repository 'http://mirror.kna1.citycloud.openstack.org/ubuntu xenial-updates Release' is not signed.
2017-05-24 12:03:02.565 | W: The repository 'http://mirror.kna1.citycloud.openstack.org/ubuntu xenial-backports Release' is not signed.
2017-05-24 12:03:02.565 | W: The repository 'http://mirror.kna1.citycloud.openstack.org/ubuntu-cloud-archive xenial-updates/ocata Release' is not signed.
2017-05-24 12:03:02.565 | W: The repository 'http://mirror.kna1.citycloud.openstack.org/ubuntu xenial-security Release' is not signed.
2017-05-24 12:03:02.565 | W: The repository 'http://builds.midonet.org/devstack unstable Release' does not have a Release file.
2017-05-24 12:03:02.565 | W: GPG error: http://builds.midonet.org/misc stable Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 8DDA494E99143E75
2017-05-24 12:03:02.565 | W: The repository 'http://builds.midonet.org/misc stable Release' is not signed.
2017-05-24 12:03:02.565 | E: Failed to fetch http://builds.midonet.org/devstack/dists/unstable/main/binary-amd64/Packages 404 Not Found
2017-05-24 12:03:02.565 | E: Some index files failed to download. They have been ignored, or old ones used instead.