Matthew Dickinson writes:

GWR services between Redhill and Gatwick Airport don't appear in the 2016 tube and rail map.

It's unclear whether they'll actually accept Oyster and Contactless from the 11th.

And does Redhill have platform Oyster validators for passengers changing
to/from the Reading-Redhill line? Or do such passengers have to exit the
gateline and re-enter using the other ticket format?