Re the flashes.
Tonight (17 October 2018), at around 20:00 Hrs UK local, I was sat out in the garden.
The weather is unseasonably warm and it was (is) a pleasant evening.
The Sun had set about an hour and a half ago.
Sky is slightly hazy, with some wisps of high cloud.
Could see the stars coming out and one or two satellites passing by.
There was a quite bright flash to the North East at about 45 Degree elevation.
At first I thought it was a plane strobe. But it was just the one flash, and the sky was clear enough to see any other light that may have been attached to a plane.
About three minutes later there was another flash. This time more to the North.
This happened four times, each about three minute apart and each from a position along an imaginary line from North East to North on a descending elevation.
At this point I ran out of sky behind the house.
As the flashes were apparently on a line, It would give the impression it was either a high flying plane with no normal light configuration, or maybe a rotating satellite reflecting light from a solar panel.
But the flash was very short and quite intense.
End of report.
HAL.