A newscast reports Eric Slater as 76 years old. But later, a newscast reports him as 73 years old. Plus, the newspaper cited him at 70.
The police find a buried Midland Bank (now HSBC) card and find it was last used in a pub in the 70's.
The is NO WAY a bank card could be used in a pub at that time. All a card could do then was guarantee a cheque or take cash out of a cash machine (ATM). The card wasn't a credit card so had no ability to pay for things on its own. Plus pubs in those days were almost exclusively cash businesses. No. In the interview room, she explains the how and why, so even if it isn't true in real life, it's used this way for the purposes of the plot.