SOLVED. YA? Sci-fi? Main female character's nickname is Bitts, short for Elizabeth? She somehow fell into a parallel world, I think a doppelganger took her place, and her male best friend had to figure out how to get her back? [s]

[Margo]

So I read this book series WAY back in the day, at least six to ten years ago, I was either in middle or high school. I'm pretty sure it was YA. There was a second book that may have included King Arthur arriving in modern times? I believe there was also a third book, but I don't remember reading that one, just a blurb at the end of the second book. I'd just love to know what this series is, or if I've somehow completely made it up

[Tab]

Ripple Effect ?

The series is the "Time Thriller Trilogy"
https://www.goodreads.com/series/6205...

The King Arthur book is the second one, Out of Time

[Margo]

Oh my god yes that’s it! Thank you so much!