Can anyone tell me why sometimes when I upload images onto fanpop it allows me to upload unlimeted images at a time and other times it only allows 20 at a time?

What I understand is that the number of images you can upload is determined, in part, by the medal you have achieved in the particular club. So if you have a fanatic fan medal in one club, you may be able to upload more images than a club for which you were a dedicated fan or for which you had no medal at all (I believe that, with no medals, an user is limited to 10 images at a time). Sadly, this sort of rewards bulk uploading with even MORE bulk uploading, but what are you gonna do?