Can I upgrade vBulletin if I use a custom style and continue using the style?

[Chunky Monkey]

Hello,

I have tried installing styles made for versions of vbulletin older than 3.7.4 and vbulletin would not allow me to do it.

If I were to find a vBulletin 3.7.4 style I am happy with so that I can install it, would that mean I could not use it if I were to upgrade vBulletin the next time an update is released, unless somebody updates the style as well?

I would like to get away from the default style, but don't want to be unable to upgrade because it would deprive everyone of a custom style they'd become accustomed to.

Can you please tell me how this works? Also, can vb styles made for earlier versions such as 3.5 be made to work with 3.7.4?

Thank you