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If I have a Premium Membership and purchase another, what happens to the existing Premium Membership?
If you are a Premium Membership and wish to extend your current Premium Membership time, this is not a problem. Any time you have remaining when purchasing another will be added to the new one.
For example, if you have two months left on your current Premium Membership when you purchase a further three months, then your Premium Membership length will be extended to five months. You will not lose any time remaining.