Anyone taking advantage of this offer? Any advice on what stations to get off at and what to see, as I've never been in this area?
To thank you for your patience during the delay in bringing the new trains into service, the Mayor of London, Sadiq Khan, has secured a month of free travel on London Overground's Gospel Oak to Barking services. This is being funded by Bombardier Transportation which makes the new trains.
Free travel dates
We are giving one month's free travel for journeys made on London Overground's Gospel Oak to Barking services between 31 August and 1 October 2019 (inclusive).
You must have a valid ticket or validated Oyster, contactless card or device to travel on this route during the month of free travel. If you don't, you may be charged a penalty fare.
The free travel will be offered through a refund. You will be refunded for the Gospel Oak to Barking part of journeys between 31 August and 1 October 2019 (inclusive) based on the full single pay as you go fare. Anyone travelling on the line during these dates will be eligible for the refund - it will be issued for every full or part journey made on the route.
https://tfl.gov.uk/modes/london-overground/gospel-oak-to-barking-improvements