Just so you know, if you're paying for Premium for you own account and you accept a Premium Family invitation, then you become part of a Premium Family plan. After you've become part of the Premium Family plan, you'll no longer be charged for Premium.
If you, however, have any Premium time on your account and you haven't used it, no worries - it'll stay on your account. This means that if after some time you leave the Premium Family plan, the Premium time you had left will be activated and you'll still be able to enjoy it.
If the case is that you're going to be the manager of the Family Plan and have just paid for Premium, you'll be able to subscribe to Premium Family but will be charged earlier for the next month due to the price difference between the two subscriptions.
We hope this helps, let us know if you need any more info on anything Spotify-related 🙂
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