Below are cut n paste of some interesting bits of the Network Rail Strategic Business Plan http://www.networkrail.co.uk/aspx/4357.aspx

Quote
Date  Service enhancement                                                  Infrastucture Enhancement              Output                                                        
2012 12 car trains on c2c mainline                                        Platform train dispatch equipment    Increase in peak capacity
2012 12 car trains on Tilbury loop and Ockendon branch         Platform extensions                        Increase in peak capacity

On the c2c route it is assumed that either additional 357 units will be ordered or that class317s will be cascaded from West Anglia. It is calculated that around 20 additional 4 car units will be required and calculations show that is space for berthing these trains at East Ham and Shoeburyness depots.

An option to improve line speed on part of the Thameside route, which could contribute towards additional capacity or improved performance, is currently being considered. Work on the business case indicates that this scheme will be worth pursuing and the project will be funded from the NRDF.

Platform lengths
It is generally accepted that the practical approach to continued passenger growth is the incremental lengthening of trains, especially as this solution is flexible, caters for the wide range of different growth scenarios and makes better use of scarce and high value paths.

c2c The key performance issues and opportunities for this route have been identified as

• accommodating more and longer freight trains associated with traffic growth from the port of Tilbury;
• improving the condition of the overhead line through campaign changes of expired components;
• reducing the impact of trespass, vandalism and fatalities;
• reducing the impact of cable theft, focusing on protection of the return conductor;
• initiation of a ‘Right Time Railway’ project focusing on sub-threshold delays, the 2nd largest cause of PPM failure;
• timetable review to cater for passenger growth, focusing on the Tilbury services and increasing seating capacity country side of Pitsea;
• faster repair of S&C; and
• improved protection of the 650v signalling supply which is prone to rodent damage in urban areas.

enhancements to be completed by end of current control period:

Date      Project                             Description                                                                            Output
2007/09 West Ham additional calls  Alterations to signalling headways and check on station capacity Increased capacity
2007/09 Grays 8-car Bay               Extend Grays Bay platform to 8-cars                                        Relieves peak overcrowding and saves 2x8 car units. Reduces EC4T costs and improves performance
2007/09 linespeeds                       Improve speeds between Barking and Upminster                       Reduce journey time/ improve performance buffer

Proposed enhancements for control period 4

Date      Project                                                                                             Description                                                           Output
2009-13 Power supply upgrade -                                                                     Provide power supply to support longer trains and additional services
2012      Platform extensions on the Tilbury loop and Ockendon Branch              12 car platform extensions                                       Improved capacity
2012      Platform equipment for longer trains                                                  Platform equipment to facilitate train dispatch             Improve capacity and performance
2012      Minor power works                                                                           Minor power upgrade                                               Support capacity improvement

Candidate Schemes for Conrol period 4

2012      Ockendon Branch loop at Upminster                                                   Provision of loop                                                     Performance improvement
2012      Fenchurch St and Chafford Hundred Passenger circulation                    Improve circulation                                                    Capacity improvement
2010      Laindon improved access                                                                  Additional access                                                    Capacity improvement
2012      Platform equipment for operation of longer trains                                 Equipment to facilitate the dispatch of longer trains     Capacity and performance improvement
2010      Shore supply to Shoeburyness depot                                                  Provide supply to depot when line is isolated              Improve performance

Unquote

Seems to be good news all round - lets hope the proposals are fulfilled and the candidates elected! ie someone has the money to pay for all this  

Chafford can cope with 12 car trains at present.

As for Grays plat 2 after the current extension of plat 3, I doubt it will have signalling to cope with 12 car trains, as the point of the bay extension is to allow the turning of 8 car trains without blocking the mainline. Thus any changes will be limited to acheive this aim, also I'm not sure that extensing plat 3 to 8 cars will necessarily create a 12 car plat 2.

Anyway if it were to be used for 12 car trains, we go back to the situation we currently have - the mainline is blocked whilst the train turns - thus reducing capacity the bay extension seeks to overcome. Also I doubt c2c would want to run trains that missed Ockendon, this will just exacerbate the overcrowding issue (on the trains that eventually DO stop at Ockendon)

Lets just hope they get they get Chafford Hundred right this time, also agree something has to be done about fenchurch, the top concorse is like the dogems' in rush hour.