Rest day today. No running and no beer..
My best chance to duck under 2hr30 will be to replicate my plan in Dublin. Try and get to half-way in good shape somewhere around 1:14 low and then hang on. The big thing, and I'd say this is where luck comes into the race is to get in a group. I can't stress how important that is - it makes the execution of the race so much easier if you have others around you to work with. London gets big numbers so I'm hoping there will be a few like minded people shooting for sub 2hr30.
Pacing required - 3:33/km or 5:43/mile.
The big lesson learnt from last time I raced London is to not get too carried away at the start. Easily done as it's like being at the Olympics. Crowd everywhere cheering you on. Don't run your race in the first 10km...slow and steady...open up the throttle at 20 miles if you have anything left.