Welcome to planDisney, Michael!
Michael before you change your
Disney Park Pass system reservation, you will need to check and make sure that the dates that you would like are showing as open on the
availability calendar.
If your new dates are available, you will need to log into your
My Disney Experience Account and click on "My Plans." Here you will be able to see your existing reservations. Once you see a reservation for a day that you would like to change, click on it and select "cancel."
After you have canceled your reservations, you may then go to the "Disney Park Pass system" and create your reservations for your new dates!
I hope that this answered your question, Michael!
Have a magical time!
Sarah B.