A.C.
I don't know any preschools in Frisco, I'm in Flower Mound. But I wanted to put in my 2 cents. That preschool sounds expensive to me...a price increase of over 35%? That sounds ridiculous. I've heard from many parents who have tried both expensive and cheap preschools with their kids, and most say that their kids were just as prepared for Kinder going to a cheaper preschool. If it's the $ you're worried about, I would shop around...try local churches in the area, those seem to be the cheapest, around here anyways. But then again, if you REALLY love the preschool where she is now, it might be worth it! Just obviously make sure it's a place both you and she are comfortable with!
Personally, I put my kids in preschool for 2 years before they go to kinder. Right now, we are paying about $135/month, for T/Th classes, from 945 - 1. It's held at the local rec center, which I think is a big reason for it being cheaper.
Also, as you're looking around, I find the best way to compare prices (since there are different times, days of the week, monthly pricing, etc.) is to divide out how much you are paying per hour of her being in school. Good luck!