You can switch SAs at any time. I don't know of any SAs at the boutique at Wynn in Vegas, but if you would like an absolutely wonderful SA in the South Coast Plaza (Costa Mesa, California) boutique that you can build a relationship with I can personally recommend Christina. She's absolutely amazing - very kind, is incredibly passionate about jewelry but not pushy at all, & responds timely to any texts / calls! Having her as an SA feels like shopping with one of your best friends. If you would like her contact info, let me know.