The changes in the status of the lights as reported make perfect sense if Sheila carried out the shootings. Whether Jeremy or Sheila is guilty, we do know that from what unfolded,either reloading or second guns involved, Neville's presence in the kitchen and the number of bullets that hit their intended target, that it is surely more likely that lights were on as the incident unfolded.
At 4.09 the lights are reported as being all on. Again this makes perfect sense in a scenario of Sheila having committed the killings. It is just prior to this that the police arrive on the scene. Sheila having just killed everyone in the house is now faced with police turning up to the house. It is not too much of a stretch to see that this new turn of events may cause Sheila to observe from the inside what was unfolding outside. We can reasonably infer that she would probably turn off the light in the room before making her way to the window to observe the unfolding scene.
The original logs which EP have failed to disclose would no doubt clear up the matter of observing the act of the lights changing status. Perhaps this is why the original logs have never been disclosed for ESDA testing. I am pretty certain that EP would not be stupid enough to leave references to seeing a light turn off and this may explain the coyness of EP in this matter. It is difficult to think of a good reason why EP have been so obstructive on this matter.
It also lends credence to the movement in the window observed by Bews, Myall and Jeremy by which time the light was out.
Mat's unconvincing and not believable explanation that, "Officers unfamiliar with the house disagreed with what lights were on/off from where they were standing", to explain these discrepancies is barely worth consideration.
From what has been learnt over the years about EP and their removal of and tampering with evidence eg. photos, logs etc., there are reasonable suspicions that evidence which would clearly exonerate Jeremy is exactly the evidence that has been removed/tampered with. Surely nobody is naive enough to believe that the log disclosed by EP would have an entry specifically stating that a light was seen going off.
It is not feasible that under the circumstances of their attendance at WHF that EP were doing a half arsed observation. They had strong suspicions that four were already dead and that the perpetrator was alive and armed. There is little doubt that the observations were accurate and claims otherwise lack credence for the reasons stated. EP were setting up for what they believed a siege situation with an armed person.
It is obvious that the changing status of the lights cannot have been Jeremy, so to maintain belief in guilt it is necessary to claim that several separate observations by police officers who believed themselves in a siege situation with a suspected armed and dangerous individual were as a result of them not really paying attention.