Hi Zoe! Welcome to planDisney! We love getting to help Guests get answers to their planning questions. I'm so sorry to hear that you need to make last-minute changes to your Disneyland Resort visit.
I'm happy to report that you can definitely cancel your current reservations and then rebook your ticket reservations for new dates. All you need to do is log into your
Disney account. Once you are signed in, hover over "My Disneyland" and click on "Ticket and Reservation Details". From there, click "View My Park Reservations". Now you will be able to see your upcoming reservations and be able to cancel. This will walk you through canceling the days/tickets you need to and also allow you to rebook if you have your new dates in mind. Should those not work out, again you can cancel and rebook as long as the days you are trying to book still have availability for reservations.
While you are deciding on your rescheduled dates, you can check out
Disney Parks Blog to see the latest announcements on what upcoming events and special entertainment will be coming to Disneyland Resort.
Zoe, I know canceling last-minute plans is quite the bummer, but please know that no matter when the right time for you to visit The Happiest Place on Earth might be -- you've always got a friend in us here at planDisney to help you with your questions. We hope to see you soon!
Carrie