The question in summary is what fare should I pay using Oyster PAYG if I
travel from zone 2 to zone 1 via zone 3?

I know I ought to be able to find the answer to this within TfL's
material but I have failed so far.

And it is a practical issue for me. I commonly use the North London
Line from Homerton to Highbury & Islington and then on to central
London. But when the Victoria line is closed or there are other
problems with that route I may travel to Stratford and then use the
Jubilee line. I don't touch any transfer pad at Stratford (and don't
see any I could touch). So I am charged only for a zones 1-2 journey.

Is this right or should I be paying for a zones 1-3 journey please?

If I should be paying for a zones 1-3 journey, how/where ought I to
touch at Stratford please?


[1] I say "as was" as the TfL don't seem to use the term. But I don't
know then how they distinguish the different bits (chunks? legs?
appendages?) of the Overground.

--
R