AstraVanMan wrote:

Ah right - that's one thing though - on the "Your guide to Oyster" leaflet
it says that the deposit is refundable. I quote "When you first get your
Oyster card, you will need to pay a refundable £3 deposit if you are buying
a 7 Day Travelcard or using cash to pay as you go."

So if it is refundable, when does the refund happen, or is it in the form of
credits towards journeys or something?

You get the deposit back when/if you give them the Oyster back.