This is being discussed in the http://gbatemp.net/threads/002-0102-ban-bypass-method-more-info.449181/ thread, however I believe this deserves more visibility for the forum members. Just minutes ago Nintendo started a new 3DS banwave, however, this time there doesn't seem to be any apparent reason for being banned. Seems like Nintendo is just banning CFW users randomly. Users report getting banned on both AL9H and B9S. Of course, there could be an underlying reason for this, but for now, be cautious about what you do to prevent getting banned and wait for further info.