I was just trying the latest bb-learn-9.1-Q4-2016.box
$ vagrant ssh
Welcome to Ubuntu 15.10 (GNU/Linux 4.2.0-42-generic x86_64)
* Documentation: https://help.ubuntu.com/
Get cloud support with Ubuntu Advantage Cloud Guest:
Your Ubuntu release is not supported anymore.
For upgrade information, please visit:
New release '16.04.1 LTS' available.
Run 'do-release-upgrade' to upgrade to it.
Should we need to do the 'do-release-upgrade'?