Here is an extract from the AD explaining why it has been issued
Origin of this new AD
Further to a new fracture in flight of a CAP 10B wing in June 2003, the investigation in process seems to point out that a wrong application of CAP 10B Service Bulletin N° 16 (CAP 10B-57-004) would lead to the impossibility of detecting the potential spar damage while performing the Type Certificate holder upper spar flange inspection.
While waiting for the results of the Type Certificate holder investigations, new operating limitations are enforced by this AD that replaces AD 2001-616(A)