I?m sorry for keeping you waiting with the reply.
Indeed there were some problems with counting the rebills, but as soon as we noticed that we fixed the problem and as a compensation for the inconvenience we paid all the affected webmasters the whole rebill amount. Check the screenshot bellow. The rebill was made on March 31st 2012. We added 39,95 $ on April 3rd 2012.
Once again this issue is solved now and all signups and rebills are counted correctly. Please accept our apologizes.