I thought I was pretty set in my fictional what-if but re-reading some of my research material got me thinking that it might be nice to add a little Lancashire & Yorkshire spice to the mix. In my original scenario the L&Y gained some running powers over the line through ficticious Heathley but it's not really clear how they would have used it. The answer was quite simple and staring me in the face. In reality L&Y Leeds/Bradford trains were joined or split at Low Moor with Leeds portions using the Bradford avoiding lines at Bowling Junction through to Laisterdyke. There was however a little used GNR branch linking Low Moor with Dudley Hill where there was a north and a south facing junction onto the Laisterdyke-Ardsley route. Traffic was disappointing and the line was short lived, opening in 1893 and closing as early as 1917 and it's doubtful if the south facing junction was ever actually used. Remains of the line can be seen here and I believe the GNR goods shed at Low Moor still survives in industrial use here.

In my reality this line has remained open and some L&Y trains will run to Low Moor and then across GNR metals to Adwalton and down through Heathley Kirkgate to Heathley Central, then through East Pudsey returning to the 'real' route before reaching Leeds Central. Although it's a slightly roundabout journey, Heathley is meant to be a large town so it wouldn't be unlikely that some trains would use this route. This provides an excuse to use some stock and motive power that otherwise would have been slightly tenuous such as Jubilees, Patriots and Scots on services across the Calder Valley to Liverpool Exchange. It also gives more scope for local services running between Low Moor and Leeds.