Had another oddity.
Highbury & Islington to Harlow Town is £13.90, where I would expect it to be £11.90 same as other Zone123 to Harlow off-peak fares. Strange that Highbury & Islington is priced higher than zone 1.
But I got a cap applied that day anyway.
Harlow to Zone 1 peak was £15
Then a separate zone 1 underground peak £3.10
Finally Highbury & Islington (via Tottenham Hale on Victoria line) was £13.90 (I expected £11.90) but capped to £11.20
This means I paid £29.30 for the day, when I was expecting £30.