Hi there, Jasmine, and welcome to planDisney!
We're so happy that you came by with your question and it's always nice to see another fellow Magic Key Holder here!
I'm happy to report that you should be able to do exactly as you stated. Your situation is very similar to mine because I have a
Magic Key that is due to expire at the end of the month but I'm unsure when I'll be traveling to the Disneyland Resort next. So when this Magic Key sales window opened, instead of renewing my old Magic Key, I just purchased a new one so that I could have the freedom to activate it whenever I wanted (within a year from the date of purchase). It's perfectly fine to have multiple Magic Key Passes attached to your MyDisney account.
Be sure to read through the
Magic Key Buying Guide so you know what to expect. As we've seen, Magic Key sales can be unpredictable, so I would make sure to have my new Magic Key purchased before allowing your old one to expire because late renewals are not allowed.
Jasmine, good luck with your decision and thanks again for coming by! Please feel free to write back anytime you think of more questions. We're always happy to help!
Wishing You a Great, Big, Beautiful Tomorrow!
-Al