Hi DeeDee!
Frozen Even After is absolutely enchanting! I'm so glad you are making it part of your plans!
Based my family's experience, the best time to experience Frozen Ever After without a
FastPass+ is at park opening. If possible, try to arrive at Epcot a few minutes before the theme park opens and go immediately to the attraction. We did this on our last trip to Walt Disney World Resort and our wait time was very short.
Another great time is during
Extra Magic Hours, for Guests staying at a Disney Resort hotel. Based on your arrival date, I believe you will have evening Extra Magic Hours the second night of your visit.
Regardless of when you set sail in Arendelle, you are going to love every moment of your journey. Queen Elsa, Princess Anna, Olaf, Kristoff and all their friends will be so excited to know you are planning to join them for their Summer Snow Day!
You will be at Walt Disney World Resort in a few short days! If you need any other last minute tips or advice as you put the finishing touches on your vacation plans, please let us know. Thanks so much for sharing your question with the Disney Parks Moms Panel. Have a magical Walt Disney World Resort vacation!