In any event, Neville Bamber body was much closer to the kitchen door at the time police entered the farmhouse, than where it eventually ended up being photographed - his body was seated on one chair, with his head and shoulders resting on the back of a second chair which his killer had placed there to support his upper body and to prevent it from toppling over! Whoever that person was who sat Neveille down like that never intended police to come into that kitchen through that door...
But cops did, they toppled over Neveilles body and staged his death scene prior to 10.00am when PC Bird (second team of SOCO) captured it in photographs...
Seems somewhat obvious to me then that the back stairs were not accessible to the killer after Neville Bambers body was staged like that!