Comment 4 for bug 1317371

I am upgrading -- I already have the previous Ubuntu dual boot system installed, and am experiencing this bug.

OK, I think the problem is that the app update is not actually being downloaded. Follow the bouncing ball:

If we specify "dualboot.sh update" (with explicit "update" parameter), we do this (lines 361-4):

    elif [[ "$ACTION" == update ]]; then
    echo "Dev:$DEVICE_ID: selected update install"
    download_app_update
    install_ubuntu_installer $UBUNTU_INSTALLER_PACKAGE

but if we do not specify a parameter, then we go into auto_mode (lines 372-3):

    echo "Dafaulting to auto action"
    auto_mode

and auto_mode then detects that an update is needed (lines 213-4):

        echo "selecting UPDATE mode"
        install_ubuntu_installer $UBUNTU_INSTALLER_PACKAGE

but note that it does not run download_app_update!

Explicitly running "dualboot.sh update" does download the app update, and makes the sideload error not occur, and the script completes without error.