"Boltar" wrote

and when ELLX gets to Highbury & Islington the NLL tracks will be AC
between
Dalston and Camden Road, and the new NLL trains will run on AC all the
way
from Stratford to Acton.

Will the 3rd rail be lifted then?

The whole lot will probably have to be relaid anyway, to provide 4 platforms
at Canonbury and Highbury, and 4 tracks on the current 3-track section. I
can't see the juice rail surviving all that (except on the ELLX lines
between Dalston Junction and Highbury & Islington, as the ELLX will be an
entirely DC operation, and its trains, though in other respects essentially
the same as the new trains for the NLL, will be DC only).

Peter