I'm a bit embarrased to say that was it. I ruled the router out because > 10 devices still worked (wireless & wired). And the Pi got a lease thru DHCP for the wireless connection so I thought DHCP was working.
But ... have you tried turning it on / off again worked this time. I hope we get rid of the summer / winter time regime in Europe .... not logical for humans or electronic devies.
Klojum : thanks!