Hi Mike! Thanks for bringing your question to planDisney.
I have good news for you: You don't need to buy a whole new
Magic Key to get the benefits of a higher-level pass. You can
upgrade your Magic Key to a higher level so long as they are still available for sale by paying the difference. You'll then be at that higher level for the remainder of your year of access, as well as renew at that level when your window opens. Your expiration date will not change. However, you must complete the upgrade in person at the ticket booths near the main entrance. Hopefully, you can get on over there as soon as possible. Availability is not guaranteed and prices and terms are subject to change. Magic Keys are popular and there is a possibility they'll sell out.
Since you're planning on switching to a different Magic Key, be sure you're familiar with your new Magic Key's benefits and terms, including
Blockout dates. Although it sounds like you've already researched and are excited to explore the parks at the new pass level. I've got my fingers crossed you'll succeed.
I've got a similar renewal window as you, and I'm ready to renew as well. It's been my first year as a Magic Key holder, and I love having more access to the Happiest Place on Earth, fun exclusives, and great
discounts. What do you like best about being a Magic Key holder?
Wishing you Pixie Dust today!
Elizabeth