Hey there, Paula! This is such a great question - and one that has kind of an iffy answer.
First, I'm sorry you had to postpone your vacation to
Walt Disney World, but the good news is, you'll be able to enjoy the
50th Anniversary Celebration during your trip. That's like a spoonful of sugar making the cancellation a bit easier to take.
Now with those
MagicBands. The bands last just about two years, and since you are at the two-year point, there's a chance they won't work. If I were you, especially since you've never used the bands, I'd skip purchasing new ones right now, bring the ones you have from your other trip, and try them out. The worst thing that will happen is they don't work, but with the tickets linked to your
My Disney Experience account, you'll be able to use your smartphone. With
Disney MagicMobile Service, you can just pull your theme park tickets up on your phone, open your resort room door, and even check out your
Disney PhotoPass photos.
If you find that you prefer the MagicBands, you'll find them available at most of the resort gift shops and front desks, and throughout the theme parks. You'll be able to replace the ones you have when you get there.
I hope you have a magical, memorable vacation, Paula!
Anna