Are Universal tickets upgradable?

[MomtoGKC]

My mother is buying us tickets to Universal for Christmas. We have never been so are not sure if we will like it as much as Disney. I'm thinking we will get 2 day tickets (we live close, so will only go for a weekend for now) and then if we love it when we get there we could upgrade to FL resident season passes. Is that possible? There is not a huge price difference, I just don't want to spend the money up front if we decide we want to stick to Disney.

Thanks!!

 

[macraven]