Hi guys!
We're going to WDW in October for my 50th birthday - sheesh - splurging and staying at the Contemporary. 4 days/3 nights.

I saw a video where they were explaining that I could buy an annual pass and put the cost of my 4-day tickets towards the overall cost of the pass.

Questions:
Would I be able to use the pass starting the first day?
Also, if we didn't go back within the year, would it still be worth it? To get discounts, etc?

We've never considered getting one since we only go every 2-3 years but now I'm wondering if that's a mistake. Any advice or experience welcome!

Thanks!!