The way it was explained to me was:
1. Airports provide figures to a third party
2. Third part collates figures
3. CAA publish figures on their website
However, the way in which figures are reported has changed due to some new EU regulation. Airports will be fined if they don't produce the figures in a certain way. Almost all airports have made the change, the third party has adapted, but the CAA system (or website?) cannot yet accept figures in the revised format.
Don't shoot the messenger - just what I'm told...