My experience with this is that as long as the survey was conducted during the performance period (maximum of two years, as you'll recall, for individual credits), you are fine. I usually recommend that my projects take care of this survey well before the 3-month shared performance period so we have plenty of time for corrective action. Better to survey early and make improvements early than waiting until the PP and rushing through either aspect.
Great answer Dan. The real thing to remember is that while all credits have to be attempted during the performance period, not all of them will take the entire period to complete.