Hmmm...the thing is, if you score a 165, you'll only average out to what, a 162, 163? So you just have to decide if that's worth it. Also, if you don't score a 165...then you risk your average score being the same or (horror!) going down. If it stays the same, then they'll KNOW that it wasn't just situational. If it goes down...then it's definitely not good.
I think you should write an addendum and apply now, keep practicing, and if you start hitting high 160s, 170s in practices, THEN consider retaking it.