Phone-calls aside,,as this has been done to death.Let's ask another question.
Sheila was still alive at 6am,,until at least another hour later,,Jeremy was outside the farmhouse,,so how could he possibly have killed Sheila,as the house had been surrounded by police and Jeremy had been with them for over 2 hours at this point,and NOBODY left that house either through a window,or indeed a door ?
Also outside,was an alsation dog,trained in the scent of gunpowder,,which is easily detectable-------even after washing,,,but guess what,,no traces of residue were picked up from Jeremy after allegedly firing ALL those shots.