Forum 4.02 upgrade changed Avatars filenames
 

Example for one user (all avatars are now 'off' by one number):
4.02 is looking for /customavatars/avatar373_46
The avatar listed in /forum/customavatars is avatar373_47

Worked fine in 4.01. What mechanism caused this renaming of avatars and how can I prevent it from happening when I do a Live upgrade?