Although I would not trust an Ed Balls who from 1997 has advisor co responsibility with Brown from selling our gold onwards, or Farage as can't oversee his own party's general Election manifesto - the 'devil in the detail' appears to be 'the rebate' that halves the £1.7 billion.
As on the one side, I have heard from the cheap seats this rebate was what we was getting next year anyway, while on the other, it is an ADDITIONAL rebate.
Clearly if Osbourne has not halved it, he is a silly boy for not thinking we'd rumble it, but if he is right on an additional rebate, of course we'd expect apologies from 2010 'what budget deficit Brown/Balls' and a Farage whose economic maths, thinks increasing the UK budget deficit with a extra £19 billion of unfunded annual tax cuts for all with no other policies, is sound UK financial management.
One other thing Osbourne mentioned, was that the cut of the bill was a preliminary move, with more cuts possible once they start to go through the EU's math, going back nearly 20-years.
Governments from time to time 'rebase' their GDP, Consumer Price Index and other indices, to reflect changes in the economy/spending patterns, with the view to make it more accurate data.
It will take a while longer for the Treasury to go through the EU rebasing of the whole UK economy, to get to the bottom of why we had this bill in the first place - and challenges to the data will not make it go up, only down.
Anyone wanting to get all the EU facts and a democratic vote on whether we stay in or out of the EU, can only get that with one party - and it ain't the 'all Farage mouth and trousers' UKIP.