The bus was a former Stagecoach service bus (No.20780) which had worn a promotional overall advert for "Laurel & Hardy" rather than Stagecoach corporate colours. As it had been a service bus, it was not fitted with seat belts.
Photos of the vehicle (pre-accident) can be seen at
http://www.flickr.com/photos/emdjt42/3557774902/
Given the road conditions reported (fog with less than 100 metres visibility) and the report at 0612 that there was a vehicle blocking Lane 1, the Highways Agency should have switched the warning lights to channel traffic out of Lane 1 into Lanes 2 and 3 and should have despatched the Police and Traffic Officers to the scene as a broken down bus/coach full of people should be a major emergency. I would have thought that the bus driver should also have evacuated the passengers to a place of safety.
Having said that, the FW truck must have hit the stationary bus at some speed given the distance the vehicle was projected (given that its' brakes were on).
There are a lot of contributory elements to this tragic accident. My thoughts and condolences go to all of the next of kin and relatives.