My understanding of the grand plan is as per
@Allandale25's blue line: going all the way from the new bridge, merging into the existing North Track just west (south) of Bayview, where the new crossover is. Both CP lines will tie into the new blue line. What I don't know is what the crossovers will look like from the blue line over to the two existing tracks at Ham Jct. There has to be a path from the "Cowpath" (the connecting line to the CN Dundas Sub, heading west to Dundas) into Hamilton Yard, for CN freight. And there has to be some redundancy in routing for GO trains, they can't all use the blue line or there is no potential for 2 way routing. That's a very tight area to place the number of potential crossovers. And it's a big job to install them all..... and then test the signals further.
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