Thanks for your replies.
Barry...
It was a very quiet, warm and still night with very little if any noise around us. No engine noise.
No flashing/navigation lights. They were about the same brightness/size as an average star. They ‘appeared’ to be very far away, I could probably have covered the perfect circular movement they made with an out stretched thumb or two.
Both times they approached head on, stopped dead and went into the circular movement, headed off at different angles.
The first pair appeared, did their thing, I was quite animated and swearing, much to my daughter’s surprise (!) not something I usually do ! and then they disappeared, my wife and daughter didn’t see it but as I was pointing in the direction the second pair came along and did the same or similar movements, so no more than a minute in total.
I’m perhaps thinking drones now but they were way out and very high to the right of the brightest star in that direction (Deneb I think) and below us and them was probably 70 miles (?) of sea looking towards Devon.
It was quite amazing. The movements were nothing I’ve ever seen before.