So if the JP had proper markings, wouldn't that infer an accident of some sort, presumably landing, which left the thing fit only for the dump?
One can think of a few scenarios where it might have had a paint scheme before the rest of the fleet, but I haven't a clue - not my time or type.
BOAC - just saw your post re. the Herc', that does tend to fit with the rumours I heard - may not be relevant, but do the engine parts in the earlier photo's look anything like Allinson ( sp ? ) bits ?