"Mizter T" wrote

OK, excuse me for being a bit dense, I haven't entirely got my head
around these new post-ELLX arrangements on the NLL yet. Peter has
previously explained that there will be two pairs of tracks from the
junction just west of Dalston[*] to Camden Rd, and ELLX will have
exclusive use as far as H&I.

So Canonbury station will have four platform faces, one for each track
- and there will be separate platforms there for NLL and ELLX trains.
What is to happen at H&I - are there to be separate platforms as well
- and also what happens at Caledonian Road & Barnsbury, are the ELLX
trains not actually going to terminate there - or are they going to
turf everyone out at H&I and then reverse somewhere between H&I and
Caledonian Rd & Barnsbury?

Is there going to be any same platform interchange between NLL and
ELLX at either H&I or Caledonian Rd & Barnsbury? This would have
obvious benefits for the passenger, but I guess it would also have the
consequence of meaning extended dwell times at whichever station the
ELLX trains turf everyone out at - thus clogging the whole line up.
AIUI lifts are in the pipeline at H&I - for the existing platforms at
least - and one presumes that lifts would be provided for any new
platforms, so the station would at least offer accessible level
interchange for passengers to change platforms between ELLX and NLL.

December Modern Railways suggests:
Dalston to Highbury & Islington ELLX will have the southern pair and NLL the
northern pair (doubled from Canonbury) with 4 platforms at each of Canonbury
and H&I. ELLX will terminate in the platforms at H&I, though Dalston
Junction will have 4 platforms, with the outer tracks for through trains
to/from H&I and the inner pair for trains that terminate at Dalston
Junction.
From H&I to Camden Road the NLL will have 4 tracks, the southern pair
westbound and the northern pair eastbound (though two tracks will have
reversible signalling, presumably to allow service to continue if one pair
is blocked for maintenance). Canonbury is shown as having three platforms
(no platform face on the northernmost line, so this will presumably be
mainly used for eastbound freight). Camden Road is also shown as having
three platforms - from the south a westbound platform, a west-facing bay, an
eastbound platform, and an eastbound line without a platform face.
There will be a single track connection west of H&I between the ELLX and the
NLL, presumably for stock transfer and maintenance trains - the ELLX and its
trains will be DC only and presumably the NLL will become AC only west of
Primrose Hill/Acton (though will still need dual voltage stock

Peter