Can you be more specific? Do you mean that you already have an exam scheduled and you want to reschedule and you are curious whether there's a limit as to how far out you can push the exam? If so, you can reschedule as far out as there are appointments available at the test site. Appointments are typically offered about 2-3 months out from today.

Or do you mean how far before the scheduled exam date do you have to reschedule in order not to lose all of your money? You have to reschedule at least 7 days before your test date in order to pay only a $50 fee. If you reschedule within 7 days of your test date, you will lose the $250 you paid the first time and have to pay that whole amount again.

Or do you mean something else entirely? Just let us know!