On the official site, seems annis got it right last night

although there is no mention of a 48 hour call back, seems like there are no conditions attached.
PUBLISHED
08:58 12th April 2013
Cardiff City Football Club are pleased to announce that an agreement has been reached with Norwich City to allow defender Leon Barnett to remain in South Wales until the end of the season.
Malky Mackay this morning said, "Thanks to the support of Chris Hughton and Norwich City, Leon Barnett will be staying with us until the end of the season. We are very grateful to Norwich for their help and look forward to Leon continuing his impressive form in a Cardiff City shirt for our remaining games."
All at Cardiff City echo Malky’s sentiment and thank Norwich for their assistance. Leon has played four games for the club so far, growing in stature with each fixture. He will be able to play for our remaining five games, starting on Saturday against Nottingham Forest. The loan is set to end at the end of the season.