David wrote:

I have travelled Hayes & Harlinhgton - Hanwell (ZZ5-4) several times
and been charged £1.10 PAYG.
nationalrail.co.uk offers £2.10 Anytime Single and £3.10 (?!) Off-Peak
Single for the same journey.

£3.10 is the Offpeak return, the Anytime return is £3.70. You mustn't have
read it correctly...

Paul S