Chris wrote:

But most of us here I'm sure will be loading an OEP 'just in case' for
future use, so will always have oner ready to use as they don't expire.

Forgive me if I've misunderstood but surely the OEP will start working
whenever we touch in?

(BTW will OEPs be available from TfL ticket machines? Or will we have to
queue up for the ticket office for them?)