I'm having a bit of trouble with my user upgrades. I know that the user groups are cumulative, but what about if I want to remove something for the paying users? I'm using http://xenforo.com/community/resources/bd-rotating-ads.292/ as a banner system, and I want members to be able to pay a small sum to remove the banners. But this doesn't work since when they pay, they will still be both in the Registered user group, and the new "Paying users" user group. Can I remove something for a user group, or move user group altogether when that user pays? How? Wouldn't be so fun to manually move them every time. Thanks!