True, but with the limited service Guildford to Effingham Junction and the non existent SWR service at Bookham, as well as the proximity of London Bridge and Waterloo, only a couple of minutes away from each other on the Jubilee Line, commuters way well choose to use these services over a bus or a walk. This being said, this would create a bigger issue at Leatherhead and Ashtead if the normal commuters were unable to board their regular service.
I did mention the situation at Leatherhead and Ashtead before. This is probably the main cause of concern because they are exceedingly busy for both Southern & SWR and will have a much-reduced service both from Dorking and Guildford.
In terms of morning peak services, I reckon that people will still try to use their normal SWR route from London Road Guildford-Effingham Jn inclusive, as the Southern service is generally perceived as much slower (even though it no longer goes "round the houses" north of Sutton, like it used to!). Even if the passengers from the SWR services either side of the Southern ones
did end up using the alternative option, it still shouldn't cause serious overcrowding. Again, virtually nobody whatsoever uses the Southern services between Bookham and Guildford & vice versa on a normal day, so you have a good few hundred spare seats, not accounting for standing room as well.
In other words, if you are planning to use the Southern services because they run at a handy time of day, you'll be fine to board as far as Bookham, but beyond there, every train will be busy.
The evening peak services heading from London will be interesting, as the trains only really empty out by Leatherhead. There are quite sufficient numbers of commuters from London Bridge to places in the Sutton and Epsom areas, and plenty wanting to board at Epsom and travel to Ashtead or Leatherhead (Epsom is a surprising generator of its own commuter traffic, as the centre of town is so close to the station, and it's normally well-connected to all the other major local towns). I can imagine any normal SWR commuters will want to change at Epsom for Bookham and stations to Guildford, as they won't be able to all squeeze onboard at London Bridge. If they do that, they should be just about OK, at a pinch - but extra passengers out of London Bridge probably won't work very well!
Although I wouldn't be surprised to read of a case where GTR revenue issued a person with a ticket from Epsom to Guildford a Penalty Fare either on the way to or at Dorking, irrespective of the view of GWR conductors.
I would be very surprised indeed. GTR's Southern side has a mere handful of revenue staff, and they're generally not interested in catching people doing reasonable things because their normal choice of route is closed. There are much bigger revenue issues that they are dealing with at the moment.
10 coach 377s? How is that possible at most i thought each were 4 car units . At least they fit the platform at Guildford
377s can operate up to 10 coach (Metro) or 12 coach (Mainline) formations in passenger service and have done for the best part of a couple of decades now!
Guildford services are generally formed of 2x 377/3 and 1x 377/1 coupled together. The odd 377/4 creeps in, here and there, as well. Very rarely, a 377/2 unit has been spotted, but these are mostly used on the West London Line.
Pre-May 2018, most trains were formed of 455/8s, with just one 377 circuit on the Guildford route, but this was then changed for consistency to become an all-377 service (although this also results in extremely slow dispatch and permanent minor delays, because very few of the SWR guard dispatch monitors match up with 377 door positions...!).
