Have you cashed your modules in? If you haven't, they can't tell the difference between "not cashed in" and "going to resit". However, if you've cashed them in, then you've marked module(s) you are going to resit as "pending" and its therefore obvious. Also, its likley to have been mentioned in your reference. Cambridge have a specific resit? box on then CAF if you happen to be a Cambrige applicant