Installing ROS: apt install cannot find any distributions

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Running Ubuntu 19.04, freshly installed. This is the 4th time I've installed ROS this week, but the first time I hit this issue: After adding the PPA, getting the key, and running sudo apt update sudo apt install ros-(tab) displays:

ros-actionlib-msgs           ros-pcl-msgs
ros-base                     ros-perception
ros-base-dev                 ros-perception-dev
ros-base-lisp-dev            ros-perception-lisp-dev
ros-base-python-dev          ros-perception-python-dev
ros-cmake-modules            ros-robot
ros-core                     ros-robot-dev
ros-core-dev                 ros-robot-lisp-dev
ros-core-lisp-dev            ros-robot-python-dev
ros-core-python-dev          ros-robot-state-publisher
ros-core-rosbuild-dev        ros-roscpp-msg
ros-desktop                  ros-rosgraph-msgs
ros-desktop-dev              ros-sensor-msgs
ros-desktop-full             ros-shape-msgs
ros-desktop-full-dev         ros-simulators
ros-desktop-full-lisp-dev    ros-simulators-dev
ros-desktop-full-python-dev  ros-simulators-lisp-dev
ros-desktop-lisp-dev         ros-simulators-python-dev
ros-desktop-python-dev       ros-std-msgs
ros-diagnostic-msgs          ros-std-srvs
ros-environment              ros-stereo-msgs
ros-geometry-msgs            ros-tf2-msgs
ros-map-msgs                 ros-topic-tools-srvs
ros-message-generation       ros-trajectory-msgs
ros-message-runtime          ros-visualization-msgs
ros-mk                       ros-viz
ros-move-base-msgs           ros-viz-dev
ros-nav-msgs                 ros-viz-python-dev
ros-opencv-apps

I've not seen this happen before. Any ideas? ros-melodic nor ros-kinetic nor any other distros are there. Continuing typing and it isn't able to locate the package ros-melodic-desktop-full