As I checked for several new signing players earlier, I noticed that the value of quality attributes before signing were slightly different from those after signing. Even the calculation of average of 3 categories of attributes were incorrect before signing. In your case, it is really possible that the qualities of the player have been changed.

I only checked this after implementation of new version of T11, and I mainly checked with old version.

Here is one of the examples
http://forum.topeleven.com/top-eleve...-signing.html#