Upgrading from Seasonal to Annual Pass

[got2lovedisney]

I'm thinking of taking a trip to Disney from 12/22-12/25 :xmas: (thanks to a great A/P rate! :sohappy: ) but my Florida Residents Seasonal Pass will be "blacked-out" at that time. If I upgrade to a Florida Residents Annual Pass, will I be charged the difference in rate back to January when I got my Seasonal? Or will they just pro-rate the difference for the time remaining on the ticket (expires 1/20/07)?

TIA

 

[Monty]

They'd back-date to the start of the Seasonal. Disney doesn't pro-rate.