The Authorization to Test (ATT) is valid for 90 days. The ATT contains your test authorization number, candidate identification number, and an expiration date. This date cannot be extended for any reason. Test centers may fill up quickly, waiting to schedule your testing appointment may significantly limit dates the center can seat you. If you wait until your ATT is close to expiring, Pearson VUE may not be able to seat you prior to its expiration. If this occurs, you will be required to re-register and re-pay to take the examination.