Hi MarissaP,
First off, a 660/Q46 is a strong score (it's just above the 80th percentile overall), so it's absolutely "in the range" of what BYU would find acceptable - and as such, it could be enough to get you into BYU. By extension, a retest might not be necessary. You're ultimately asking Admissions questions though, so you would likely find it beneficial to speak with an Admissions Expert about your overall profile. There's a Forum full of them here:
https://gmatclub.com/forum/ask-admission ... tants-124/If you're not planning to apply until next year, then you could certainly retake the GMAT if you like (and my guess is that some of the Admissions Experts will actually suggest it, since there's really nothing to lose). At face value though, you have a competitive GMAT Score, so your time might be better served working on other aspects of your application profile.
GMAT assassins aren't born, they're made,
Rich