Someone Somewhere wrote:

Wow - such vitriole over a policy that was developed to speed up services
in London for those of us who live there! It's not like having an Oyster
card is that much of a hardship, and nor is it like the credit on it
expires if unused.

It may not expire but I've never been able to transfer credit from one card
to another. When the discount cards have to be renewed each year you often
find either credit being wasted on old cards or a pain when one
miscalculates when cancelling the auto-top-up and finds the balancing
running out in the middle of the night.

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