How would it look for these two services to be on ECML? I think that DTG would have to change up some things for these two trains to actually work on ECML. First, they would have to work on new trains for Grand Central and remodel the Class 801 for Lumo. Then, they would have to have to make these stop at Peterborough and Doncaster for the sake of actually functioning on this route as in real life they don't stop there, they just keep going non stop for the entire line. Finally, the frequency. Frequency is not that great for both of these. Grand Central has only 20 services going on this line daily while Lumo only has 10 daily services for this line. Half of both going in one direction. But would it really work for this route? I think it could, but then again, due to not so great frequency, I don't know. Feel free to correct some incorrect things I have pointed out as don't know all of this and if it's true or not.
Given the whole point is realism, and LUMO doesn't stop between Peterborough and Doncaster, its unlikely (as in near impossible). Grand Central, given they run non stop Doncaster to King's Cross, also unlikely. However, maybe as a layer, if there is a route to either Sunderland or Bradford that Grand Central takes the stage.
As I did point out I think that they would have to bend that up a bit for the sake of being able to function on this route if no extention is made. Ex. Extention for King's Cross and Newcastle.
Though I know for Lumo on that stretch it mean sitting in a train for 3 hours without stopping between London and Newcastle, even if they try to make it stop somewhere like Stevenage.
The only way I can see Lumo in TSW is if we get Newcastle to Edinburgh, otherwise it doesn't make any sense to include a new train and paint it blue for AI only.
That is obviously the only way - only an AI layer if there is a route which you can actually drive Lumo trains on.
