Very unlikely. Height meant survival for the heavies, they needed to get out of range of small arms fire and light flack. Assuming we are not talking a coastal airfield anybody who could only make 500ft by the coast would be full justified in turning back. To continue with that lack of performance would be suicide.

Of course some raids, particularly Mosquito, crossed the North Sea a lot lower than 500ft to avoid the radar for as long as possible.

There was no ‘forming up in the sense that the 8th Airforce would, but the bombers would funnel through one of the coastal beacons (Splashers?) to concentrate the bomber stream.

Moggy