Military guy here that had to stay in for various reasons (mostly to do with BUPERS...to put it gently,) and I took that fit assessment probably 3-4 years ago now. My app 'checkmark' is still green and I've not had to re-take it due to any amount of longevity/time away from taking it. Don't know if that helps your question, but for me, no-retake required (thus far) due to length of time.