I live just a few miles from the crash site.Between Beccles and the coast,the crash site being about one mile west of the town.I was working in the garden all afternoon and only went in when it got dusk about 6pm.The three quarters full moon was clearly visible at 730 when I went back out to check on the bonfire that I had lit.
Gillingham though is beside the River Waveney and the fog forms there much more densely and often in patches.My guess is that they decided to fly and were in one of the less dense parts but quickly ran into a patch.My wife came in about seven and said she ran into some thick stuff that was clear after a couple of hundred metres.