I am currently in a byobu-tmux session and am ssh'ed into a screen session. How do I detach the remote screen session without detaching byobu-tmux session? Some things to note, I can't run byobu-config because I'm on osx and don't have python-newt (w/ snack) installed. And, I've run byobu-ctrl-a in Emacs mode, but that doesn't seem to allow me to ctrl-a d out of the remote screen session.
You should be able to double-escape with Ctrl-a.
To send a detach message to the inner byobu-screen session, press:
Ctrl-a Ctrl-a d
Full disclosure: I am the author and maintainer of Byobu.