pulsating high altitude light

need some ideas on this one.

Seen late at night I.e 3/4 am uk time, direction of travel south east / northwesterly direction.

Bright yellow pulsating light with no sound flies over at high altitude, then dimms to orange / red colour, and makes a steep dive in the direction of Brize Norton as seen from oxford. Ie north west.

What makes this intereting is that we know roughly when its going to be coming over, as about fifteen minutes before, a high altitude hercules flies over and streams out a chemical that makes fine high altitude clouds.

The comes the pulsing on the horizon, and in drops this light (Or what ever it is). The reason we have seen it in oxford is that at times the herc just cannot make a deep enough cloud cover at times to hide the light.

Thats all the info i have folks, apart from that this light started to fly over in jan 2005, and that the herc flies the same flight path as the light. any info appreciated.

If you know It's coming 15 mins beforehand could you please film it ,I'm sure many members would like to take a look.