Ok I think I got the place. Been there a couple of times and is very pleasant, although a bit away from Central London, but easy to get there.
It is a Wetherspoons, so reasonably priced.
If you don't mind to get to East London, canary wharf, this is a nice big place:
The Ledger Building (Wetherspoons)
West India quay
Can use the jubilee or DLR to get there. Should be easy to find a bike spot on a Saturday.
Or if you prefer to feel a bit like James Bond, get on one of the Clippers boats!
Hope to see you there round 1pm on the 16th then!