A quick update to my migration process.
I had all the servers running 16.04 and it was OK except for the stability. Setting up and moving things were simple enough. I did encounter issues with my symlinked .bashrc which I couldn’t figure out. The version was set and running a stat on the symlink also showed it found the file.
I found the containers to be up and down on Docker. The containers were still running 14.04 at the time and whilst I am running 2 full LAMP / nginx stack on 512mb it would keep going down with nothing to note in the logs. I suspect it could be memory related but due to the instabilities I moved back to 14.04 before taking another look at it again.