From the Tickets FAQ at disneyworld.com LINK:
Q. How can I determine the number of days remaining on a theme park ticket?
A. When you arrive at Walt Disney World Resort, please show your ticket to a Cast Member at any of the following locations:
Photograph or scan of the front and back of each ticket
Photograph or scan of a government-issued ID
Your full name
Phone number where you can be reached during the day
Please keep the total email size, including attachments, below 2 MB. To ensure your email is less than 2 MB, you may need to compress your images or send multiple emails.
We’ll try to get back to you as soon as possible, but it normally takes 14 business days for a response.
You can link your ticket to your MDE account and begin booking FPs. The number of days that MDE allows you to book FPs is the total number of days remaining on your ticket. After you have determined the total number, cancel all of the "research" FPs.
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