Something else that I didn't expect.
As far as I know, the Luton airport DART is nothing to do with TFL.
I expected to be charged £4.90 for using the DART, and that would be completely separate from the journeys around London later that day.
At the entry to the DART, there aren't any obvious gates to tap in. A staff member did point to a ticket machine, but said we could simply tap out on exit, and pay that way.
So we just tapped out at the exit from the DART.
Later, I was surprised to see the DART journey on my TFL account, listed as an Incomplete Journey.
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