Heigh-Ho, Heigh-Ho, Arne!
It's off to your answer we go! Welcome to planDisney, and thank you so much for stopping by with your question. It looks like you will be visiting Walt Disney World during the merriest time of year. It's one of my favorite times to visit Walt Disney World because not only are the parks and characters dressed in their jolly best holiday gear, but you also get to see the big cheese (and I don't mean Mickey) - Santa Claus himself!
Arne, I double-checked with Guest Services. Typically, all active tickets can be upgraded. You should be able to do so in your My Disney Experience app, as long as you
purchased your tickets separately from your Disney Resort Hotel stay. If you used
Disney Vacation Club Points for your stay, then your ticket purchase is automatically separate.
To upgrade the two-day tickets to three-day tickets, go to your
My Disney Experience app and log in to make ticket modifications. Navigate to "My Plans" and then select "My Tickets and Passes." Scroll through until you find the ticket you wish to modify, and select the option to "Change Ticket." You will be able to add days, add the Park Hopper Option, or adjust the dates of your ticket. If you add days, you will be prompted to pay the additional cost of your upgraded tickets at checkout. You should be able to select which Guests are getting the upgraded tickets so that you do it just for two of the tickets. If you have trouble doing it in your My Disney Experience account, you can contact Guest Services by phone or visit a Guest Services window on your first day at the parks. As long as you have days left on your ticket, they should be able to do that for you.
We just added an additional day to our tickets when we visited in March, while we were at Disney. I just purchased a single-day ticket for our extra day. However, it is more economical to upgrade your ticket from a two-day to a three-day ticket, because you get a discount on the per-day ticket prices with a multi-day ticket vs. a single-day ticket. So, my recommendation would be to upgrade your tickets to add the extra day or two as soon as you decide to do so.
I hope this helps you, Arne! Be sure to visit
EPCOT's International Festival of the Holidays during your visit. My favorite things are the cookie stroll and holiday storytellers in each of the countries. You can grab a guide at Guest Services to know when each will be appearing, so you don't miss a minute of the magic!
If you have any further Disney vacation planning questions, soar back here to see me, and I'll be so happy to help you. I'll be right here, at the second star on the right and straight on 'til morning.
See ya real soon!
Keri