question about tickets

[MDH]

I have a non expiring ticket for a child. If we don't end up going for 3 years, that child will now be 11. Can I just pay an upgrade fee for that ticket to change it to an adult ticket?

 

[Robo]

I have a non expiring ticket for a child. If we don't end up going for 3 years, that child will now be 11. Can I just pay an upgrade fee for that ticket to change it to an adult ticket?

It's likely that you'd pay the difference between what you paid for that ticket
and a new adult ticket.

When and from whom did you buy the ticket?