I thought I'd post my Dad's 'testimony' here, as opposed to starting another thread. I was also there at the time, but being only 11, I remember very little of the experience personally, although I do recall the night in question.
We were staying at my Nan's house, in Herne Bay, Kent (England) as sadly my Grandad had recently died and my Nan was in the process of moving to her second home that was much nearer her family. We were there to assist with packing and such.
My Dad always has been (and still is) very keen on aviation and often would spend the later part of the evening listening to his 'air-band' radio and the chatter of the pilots / control tower technicians, etc.
Anyway, this particular evening in the very late Summer of 1991 (I can get actual dates from my parents shortly), my Dad was out in the garden listening to his radio and my Mum, younger brother and I were in the house. My Brother and I were getting ready for bed (it was approx. 10:00PM).
My Dad then called 'Lin! Come here, look!' to my Mum, who we naturally followed out to the garden to see my Dad pointing up at the sky, directly over the garden. There, moving away from my Nan's house, in the sky, were 6 individual white lights, organised in the shape of two 'overlapping' triangles (sort of like a six-sided star). The radio was just emitting fuzz and jitter at this point (which was usually silent between 'normal' transmissions).
After around a minute, the object had moved too far over the back of the garden to spot and the radio kicked back into life.
Could well be a very prosaic explanation for this. I even recall asking my science teacher when I returned to school the following week as to whether there were any other aerial objects that could might pass over head at far lower than a standard plane would (bare in mind, I was young and didn't really realise how unlikely this was!)
The reason I suggested the item looked like two overlaid triangles (as opposed to the star-shape) was because the individual triangle points would inverse themselves as the object was moving (hard to explain and difficult to draw whilst at work!). So effectively, the top point of the first triangle would move down as the bottom point of the second triangle moved up. When they had reached the position that each other had previously occupied, the process resumed again. This occurred with all points of the triangles and the transition was very smooth.
Also important to point out that there was no sound audible apart from the radio chatter.
My reflective thoughts on this were that it 'could' have been some sort of laser show going on somewhere. I saw one since that reflected off the clouds and for about 3 seconds I was CERTAIN ID4 was on it's way.

And perhaps the radio interference was just coincidental.
However, whatever it was, it was certainly a strange experience and one that my Dad 'testifies' to every time we're around with all the family on Christmas night.