i paid for 2 crossings upfront a while ago, making the journey a week or two later. when i went to prepay for another 2 crossings recently, i found i was still in credit by £2.50 from the previous occasion - presumably the ANPR system is a bit hit 'n miss....... :-)
Do Blackwall its not much of a detour - or go over before 6 and after 10. I came over a few days ago and was amazed at the number of people doing 50ish on the M2 so they arrived at the tunnel after 10.
I used the Blackwall a couple of weeks ago, late Monday afternoon and it was OK but I then realised that the Woolwich Ferry takes cars, I thought it was only foot passengers, I'd been to City Airport so I was almost there. Does anyone use the Woolwich Ferry and how does it seem?