Yet another timeline...
Nowhere Child, episode 2: "More than William":
(03:35)
Caroline Overington: William's foster mum began searching the house and the garden. She went out onto Benaroon Drive, where she saw a neighbour, [AMS], who immediately offered to join the search.
She got into her mum's car and she drove around for a bit. And she searched on foot as well. And at one point she thought she heard a short sharp scream.
[... FFC's statement about the noise in the reeds near the bus stop...]
Unable to find William, she ran back to the house to get her phone. She was hoping to find a message from the foster father saying something like, 'Hey! What's going on? I've just found William wandering out the front!' - because William
was in the habit of looking out for his foster dad's car. And there was a text, but it didn't say 'Hey, I've got William!' It said 'Home in 5'. William's foster dad has told police that he used Siri to send that message, and that's been verified.
The foster mum ran out, onto the driveway, just as the foster dad was pulling in.
(05:14)
BBM.