On Wednesday, 13 September 2017 11:52:52 UTC+1, Jarle Hammen Knudsen wrote:
With Sadiq Khan’s ‘Hopper’ fare in effect, what should you do if the
second journey takes you over the one hour limit? Will you have to go
forward and touch your card again?

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jhk

As others have said the system works solely, on buses and trams, on when you touch in. Provided the second touch in is within the advertised 60 [1] minutes you will not be charged. While I understand your query about the written language used the Oyster system is using a long established feature that allowed for through tram to bus tickets in the New Addington area. This is why the "Hopper ticket" was launched so quickly after Mr Khan became Mayor - it was just a case of entering different modal info into the system.

The more complex "unlimited bus/tram rides within 1 hour" and "get second bus ride free after a tube/DLR/Train/Overground journey if within 1 hour" functionality is new and is planned for introduction in "early 2018" which I assume means the January Fares Revision. I also assume TfL are sufficiently confident in the software changes that they are testing it now (or will after the Sept fares revision [2]) before having to freeze system changes to allow for the main Jan Fares revision (Travelcard and NR price changes).

[1] in reality the system parameter is 70 mins but TfL don't advertise this.. It gives a little bit of "flex" in case the second bus runs late and also covers where services run at 30 min headways and may not always run precisely to time.
[2] yes there is a Sept fares change. It usually affects fares to / from Watford Junction plus some other minor tweaks by the TOCs.

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Paul C
via Google