Currently, I am running version: 220.127.116.11 and getting a message that a "Platform Update Available". Clicking on Available and after a few seconds, of blue streaking lines, the message appears that no update is available. Yet I still have the same notification and of course the red circle with a 1 in it.
Might want to reboot your hub if the update is still not available.
Settings: Reboot Hub.
When it comes back, try the upgrade again.
I am now the proud Papa of a brand spankin new Ver 18.104.22.168.
Rebooting took care of it and no lingering messages.