I have to do a cake with red BC sides and a white MMF top. I am worried that the red BC will bleed into the white fondant, does this happen? I'm clueless on this point but I think I saw a thread on the subject some time ago, can't find it now and I need to know, I must do the cake tomorrow. Anyone there know please????

Any b'cream should not bleed if it is made ahead of time. Like the night before. The fresher the color added, the more likely it will bleen.
Also try to keep the b'cream on the dry side....too much liquid will also add the the possibility of bleeding.