Hello, Chuck,
You are welcome to upgrade your Magic Your Way tickets by adding days, the Park Hopper Option, and/or the Water Park Fun & More Option. You need to make the upgrades in person at any of the theme parks or water park ticket windows, the concierge desks at any of the Disney Resort hotels, or Guest Relations at Downtown Disney.
In order to make an upgrade, it needs to be within 14 days of a Magic Your Way theme park ticket’s first use and the ticket has to have remaining admissions. If it is more than 14 days after first use or if no admissions remain, then a ticket may not be modified or upgraded.
Since there are many variables, it is difficult to give you an exact cost of the specific upgrade. You can explore the
Ticket Purchasing options to look at the costs of adding on the different upgrades you would like to the Magic Your Way ticket you already purchased. This should show you the additional charge if you add the upgrades at the start of your trip.
Wishing you a wonderful trip in June! -Kara