Comment 2 for bug 1960068

We've overcome the limitation after finding this post: https://discourse.ubuntu.com/t/automated-server-install-reference/16613/21

So wrapping your interactive script into:
==========================
  if ! chvt 3 &>/dev/null; then
    break
  fi

  export TERM=linux
  export NCURSES_NO_UTF8_ACS=1

  printf "\ec"

=====================
your script here
=======================
  #Change back to tty1
  if ! chvt 1 &>/dev/null; then
    break
  fi
===========================
brings the interactivity to subuquity late-commands