One of the anomalies created when contactless was extended to Windsor & Eton Riverside was the treatment of journeys from the Slough area to the Staines area via the two Windsor stations. A number of the fares were set up with interchanging between the two Windsor stations in mind, but no out of station interchange (OSI) was added to the system to join the two halves of the journey together. This meant that if you travelled between Slough and Staines you would be charged two single fares, one for Slough to Windsor & Eton Central and the other for Windsor & Eton Riverside to Staines. Sadly the sum of the two parts usually ended up more than the published combined fare. Furthermore, in some cases no other fare had been set up, meaning that travel was allowed via Central London at a fraction of the proper fare for that journey.
This has all been fixed with the recent fares revision on July 5th. There is now a proper OSI joining together journeys including the walk between Riverside and Central. New fares have been set up which are activated by exiting one station and entering the other, while the default fares are set at the level expected when travelling via Central London. The length of time allowed to walk between the stations is a very generous 40 minutes, so no need to worry about admiring the sights of Windsor or the river walk while you make your way.
As usual with changes to the system outside TfL’s core area, publicity has been non-existent. I stumbled upon the new fares by accident and asked both GWR and SWR about the time allowed between stations. Both companies said that OSIs are nothing to do with them and I had to contact TfL. In reality it is the responsibility of the train companies to ask TfL to set up what they have decided, so they really ought to train their customer service staff (including social media) in the details.