Premium for Family Owner: When you upgrade your subscription from regular Premium to Premium for Family, any remaining time that you've already paid for will be converted into a Premium for Family subscription, so this can bring your next payment date forward. You can review your renewal date on the subscription page.
Premium for Family Members: When you accept the invite, you're added to Premium for Family straight away. You won't be charged for your account any further - your payments are handled by the plan owner. Any Premium time you have remaining will resume if you leave Premium for Family.
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