Thanks for reaching out in the Community! We'll be happy to explain how switching subscriptions works 🙂
It's god to keep in mind that gift cards cannot be used in conjunction with already discounted subscriptions such as Spotify Student or Premium Family.
If you wan't to upgrade your existing subscription to a different one, you should update your payment method to do so. Don't worry, you won't be charged immediately after changing the payment details. The new subscription should take effect asap but you'll be charged after the Premium you've redeemed on your account expires.
Hope this helps, let us know how things go!
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