It is a proven fact we often see what we expect to see and hear what we expect to hear. If someone identified himself as Nevill and sounded like Nevill calling from Nevill's phone in the middle of the night it is likely the only thought would be about the message and how to react to it. It would be unlikely that you'd be questioning if it was actually Nevill in those circumstances?
People who come from the same area often have the same accent, and both Neville and James Bell were farmers, I just think in the circumstances Jeremy could have been mistaken in believing his father had called him and had spoken those 11 words in the middle of the night! Having said this, it probably was Neville who made that call, and he may have said that 'Sheila has got the gun', but there was no additional information provided by the caller at that time as to (a) which gun Sheila had got hold of, (b) why she had got hold of the gun, (c) what if anything Sheila had done by that stage, and (d) what if anything had provoked, or caused Sheila to get hold of the gun. Additionally, there was no information, or explanation, (e) what was meant by Neville saying that 'She has gone Crazy', (f) crazy in what way, (g) mentally, (h) violently and physically, (I) had she discharged the gun at all by that stage, (j) had anybody already been shot, (j) or shot at...
For all we know, not only could it have been James Bell who made that call to Jeremy disguised as Neville Bamber, but it could also have been James Bell who had made the 3.26am call to the police, at which time he deliberately put the blame for what may already have happenned. Or what was about to happen on Sheila, who he referred to as his daughter! This particular phone call falls into the same category as a phone call that was made in the Diane Jones investigation when an anonymous caller tipped off police that they had seen Diane Jones in the Bury St Edmunds area, after she had mysteriously disappeared from the doorstep of the home she shared
with Dr Jones, which was obviously a diversionary tactic, to take suspicion away from her killer!
The suggestion that Diane Jones simply walked off from the doorstep of the home she shared with Dr Jones simply does not stack up in view of what we now know happenned to her, and by that I mean what happened to her just before she disappeared, and what we now know became her fate afterwards!