Comment 4 for bug 1466347

There is a patch available in this other KDE bug report: https://bugs.kde.org/show_bug.cgi?id=314356

I think all we need to do is apply this patch to the Kubuntu version:
https://quickgit.kde.org/?p=bluedevil.git&a=commit&h=38f78cae2e67562bb40640a87d9f34f8e1a4f200

As a workaround, you can restore the adapter power after suspend with these commands:
sudo rfkill unblock bluetooth
sudo hciconfig hci0 up