You can link to David's comments and also the letter from the Commission.
It can be difficult to follow the discussion but essentially it is this.
The UK Government had posed a 26 week rule which stated that DLA recipients should have spent 26 weeks out of the last 52 within the UK to reclaim this benefit which was previously illegally removed from the recipient, perhaps some years before! The Commission make it clear that this 26/52 rule is itself illegal.
There is also debate on the 'mobility fraction' of the DLA, on which again the UK Government is wriggling.
Links (click) below..
David Burrage's note
The EU Commission's letter -the third page of this puts the situation lucidly.