Recurring NPS - Is their a set time between EACH visitor's receiving the guide

If I have NPS set to recur every 180 days for anyone who accessed Pendo in the last year.   Is the 180 days based on when any eligible segment visitor has last seen this NPS guide OR every 180 days the system looks at the segment and just randomly starts showing it to segment visitors again (even if maybe they just say it in the last month? Example -  if a visitor saw the guide day 70 after I first started the guide, then would they not be eligible to see it again until 180 days out from day 70 not when the original guide started.  Is that correct?