Why are warren street's platforms for the northern line on the outside
of the tracks, with the platform entrance so far up to the ends?

Is this something they added for the victoria line, since there seems
to have been a lot of rebuilding - there is a blocked passageway by the
escalator that I would guess used to lead to the lifts, but shouldn't
there be two - one for getting to the platforms and one for leaving?

Or is it something they did recently - the tiling looks as if it has
recently been restored, and I guess that means there must have been
some modernising like blocking off a small passage at the interchange
level that curves to the left, I guess heading down to the victoria
line, that they must have replaced by the wider one with escalators
thats used now?