Logon loop after upgrade

[Grizzlly]

Hi All

My last upgrade of Unity Noble (from working stable state) left me in a logon 
loop, at first I thought my password had been corrupted so I did the usual PW 
to recover with no change

Then I opened a terminal (Ctrl+Alt+F3) where my password did work, I ran 

apt update --fix-missing
apt -f full-upgrade

but still only get to the loop

any other ideas that "may" get me back to a GUI

I can run and post tests if that helps

Grizz