Citi frequently sends out targeted offers for American Airlines cards out via snail mail. These mailers are useful as they do not contain the restrictive 24 month language. Previously it was possible for mailers with a 9 digit customized code to be used more than once. Based on data points collected by joeyp907 on /r/churning these codes are now single use and will result in one of the following error messages when somebody tries to use the code again:
- The information entered does not match our records. Please be sure to enter it exactly as shown on your invitation letter. If you prefer, you can mail in the form attached to your invitation letter.
- For your protection, the number of attempts is limited. Please mail in your application.
RIP.
