Whoa! Aurora!

Southeast Brittany. Fairly thick cloud cover (first night of clouds in a while – damn!), however sky has a weird blue tinge like the iridescent blue on fish, and it is flashing/pulsating, fairly randomly but some parts in lines.
Pretty much all over, but seems more pronounced looking towards the east/southeast.

Sounds like the sky off to the west as a group of friends and I were travelling back from Ipswich a number of years ago. The pulsations matched the incoming radio transmission of the Bon Jovi concert taking place in Milton Keynes. We had only just branched away from the road to Diss¹ at the time. About 90 miles of nowhereville² with minimal habitational lighting and a big light source westward.

¹ The jokes about not going “Diss way” but going “dat way” went on for quite a while.
² Lots of Norfolk and Cambridgeshire in that run and most living things there have roots