I have to admit it is losing credibility with me fast. I mean, the Lotto story just didn;t hold up, them using a fake outfilt instead of the Lotto just because it made the story they devised more plausible (if that isn't a contradiction).
The killer though was Kevin getting that postcard about Sophie. Sorry, there is no way that would have got delivered in ordinary post - the moment someone in the system saw it, it would have got pulled and the police involved. The first Kevin would have known about that was when a copper called, not a postman.
And where is Jed, what's happened there? taken to hospital and nothing since.