When you create a listing, you will have the option to auto extend your listing after the listing period ends. If you allow this, you can the time will be automatically relisted if the item if a bid was placed during the last 20 second of an auction.
When this occurs, the auction countdown will be automatically reset for another 20 seconds. For example, if a bid was placed in the last 13 seconds of an auction the countdown will be reset to 20 seconds and continue counting down from there.
During this phase of the auction there is no limit to the number of bids and resets that can occur, and the auction continues until no more bids are received and the countdown times out. If auto extend is not selected, the auction will finish at the time specified when published even if bids are received in the last 20 seconds.
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