A post from Billericayspurs on SSC re transport :
Apologies in advance for a boring post.
I do produce work for Network Rail and DfT and indeed know people working in the Tottenham area on the improvements right now.
WHL is way from finishing, but the silly thing is, it will be a shiny new station, but actually it won't have any more capacity whatsoever, unless loads of extra trains are laid on (TfL dependent). The platforms are of a fixed length, to fit in with all other stations on this branch line.
Northumberland Park is the most advanced and having spoke to a member of Network Rail staff the other day, they say trains will start using the third track to Meridien Water by September which will obviously increase capacity to Stratford and Liverpool Street.
Tottenham Hale still has some track to lay and some complications with overhead power lines running under the bridge approach but again, according to my Network Rail source, will all be working by September.
Seven Sisters, once again, the station is way too small for the interchange that it is. I heard some new exits are planned to alleviate crowds. The problem with Seven Sisters is the platforms are very shallow and don't have much capacity. It is clearly the more convenient station out of TH and crowds will continue to flood this station.
I am curious as to the flow of away fans to the new stadium. Obviously they are now in the opposite corner. I am assuming the authorities will prefer them going to TH or NP but human nature always take the direct route.
On the future of rail planning, people are still suggesting a Victoria Line extension to Northumberland Park. This is never gonna happen. It's very complicated as the depot is not at the end of the line which is unusual. It would require a new tunnel and there is no money for that. Also the space that this track would take up is already safeguarded for a 4th platform at NP because if Crossrail 2 ever comes along this will be the preferred route for many as it travels from SW London up to Tottenham and then north to Broxbourne.
Currently, for me, the best way in would be to change at Stratford and head 2 stops to Northumberland Park in 11 mins. One thing I have noticed is when West Ham are at home along with Spurs, there is now a spike where opposing fans en masse are flooding onto platforms at Stratford already full of West Ham fans from OS. This will only get worse with the extra trains and bigger crowds coming from Tottenham.
My Edit - I'm sure Spurs have said that extra trains to WHL are expected which will increase capacity