Re: So where's the other £590 million gone???
The extra £1bn wasn't being handed over all at once.
It was an agreement to increase the spending budget for Northern Ireland by £1bn over a two year period.
I believe some immediate payments were made (I think £100m was released for Health and Education to release immediate pressures) the rest was to be released in the budgets for the next two years, to cover specific budget spending.
e.g. The £200m for infrastructure mentioned in the Guardian report will be followed up with another £200m the following year.