If the LE statement we're going by is this one:
"Enquiries and information received over the past week have led police to believe he may have been in the Mildenhall area at some point between 4.30am and 8am on Saturday 24 September, and police would like to hear from anyone who may have seen or spoken to a man matching Corrie’s description in this area around this time."
Then that doesn't say to me he's definitely in Mildenhall at 4.30am. All it says is that he's in Mildenhall at some point between 4.30am and 8am. Assuming this police statement IS based on phone pings, my interpretation of that would be that there was a ping in BSE at 4.30am and a final ping in Mildenhall at 8am, therefore he was in Mildenhall at some point between those times.