Redhill is really just suffering from being a busy station. It has enough services that there needs to be too many choices of platforms !. The only problem is the last minute platform changes are a killer for such a tortuous route to platform 0 from platforms 1+2.
Which they need not have created as there was plenty of room to allow Platform 1 remain a through platform and create a bay for platform 0.
Which would have meant more conflicting movements involving reversing/terminating trains and reduced capacity - which would have led to a different set of complaints.
Not sure this is right - I can't see a large increase in conflicting movements happening if swapped - we are only talking swapping P1 with P0 which are next to each other and block each other off when any movement in either on the main line from the South.
They retained the relay interlocking was the main stumbling block here limited what they could do with the layout to basically mirror image the same routes.
It didn't "have to be shortened" but was the choice taken by Network Rail when the design was fixed. Alternatives were outlined but not used.
True but it remains an unresolved conundrum
The problem is not just with the crossing of conflicting paths, but also the conflicts of overlaps at both ends of the station. At the London end there were restrictions on what simultaneous movements could be made with a modern compliant 12-car layout if both platforms #1 and #2 had both been built as through lines (with the up through line retained) The new platform #0 line has no such conflicts as it is long enough to have a full clear overlap at the north. That alignment could have been used for #1 however if #0 had been made the bay, but then anyone from anywhere would always have had to use the subway to get to or from a North Downs train using that platform. The advantage of having buffers at the N end of #1 is there's no overlap projecting north of it into the throat junction while an incoming move is made to interfere with other movements at that end. It's difficult to determine how many short notice platform changes would happen if #0 had been the bay, but clearly that would always require trains crossing more lines to access it. While such trains may be timed to avoid conflict, there are cases where it occurs anyway due to delay. There really weren't any perfect answers to having three through platfroms without widening the formation at the north, a difficult and expensive endeavour. An answer now is to build another access between all the platforms for interchange and revise the south junction layout to allow some more parallel movements. For example:
The formation narrows significantly at the footbridge just north of the new platform.
Using #0 as the main up through platform allows the various reversals and turnbacks to be handled in #1 and #2, in the middle of the layout ensuring least conflict both arriving and departing. A better layout at the south, as I illustrated, would allow up trains from Gatwick to enter in parallel with a down Gatwick or Tonbridge departure from #1 or #2 or an up Tonbridge arrival or a down Reigate arrival in #2. With less conflict in the layout there should be less need to divert trains from #0 to #2 or vice versa at short notice. I still think an extra foot transfer bridge between all platforms should be built too for the odd occasion it will still happen and to tackle the subway scrum more generally. The bridge might perhaps reuse the footings of the old P.O. conveyor bridge, like they did at East Croydon.
Should there be a platform 4 ?. For Tonbridge services to keep them away from junction conflicts - it could be off the end of platform 3 round the bend towards Tonbridge. This would beconvenient for passengers changing that arecoming from the London direction or going to the coast. Would it make life easier over on Platforms 0-2 allowing platform 0 to get less use. I am probably un-justifying platform 0 and creating more trecking for (the few ?) Tonbridge branch passengers !.
Personally I have advocated it, but like putting back P1 it is unlikely to happen Due to lack of funds. Redhill (and Reigate to some extent) will remain unloved by passengers as stations slowly dilapidating
