Your scenario of Sheila's movements on the night just doesn't hold water!
On the contrary. Sheila has to go to the office cupboard reload the rifle plus there are other targets in the house. For all you know she could have locked herself in a room with the gun and was threatning to kill herself after dispatching the twins. This prompts Neville to call for assistance. Also its not necessary for Neville to call the police BTW. You fail to consider the variables
What you cant or don't want to see is this
http://jeremybamberforum.co.uk/index.php/topic,7866.msg374113.html#msg374113
David, your scenario of Sheila's movements on the night just doesn't hold water with me! You assume the phone was in the position it was found earlier in the evening, there were 12 rifle cartridges/bullets found in the main bedroom, and one on the landing. indicating Nevelle was shot 4 times in the bedroom. The box of rifle cartridges were on the kitchen unit, not in the cupboard.
Then of course we have the liver mortis....your baby... Sorry David, but it looks like your reading the wrong info there.