UAF weren't there as far as we can tell. They usually only turn up when there is a anti-Muslim march and this doesn't seem to have been that. They probably didn't expect problems from EDL on Armistice Day.
According to
The Guardian their intended target were the protesters at St Pauls. Quite why the EDL would have a problem with the Occupy movement isn't clearly explained. Sounds like they have more in common with the Islamic regimes they profess to oppose than they thought.