The seller has enabled Bid Boost.
Bid Boost allows the seller at any time throughout the auction, to accept a bid which is at a level they are happy to sell, regardless of the time left in the original auction schedule. The new end date will be 24 hours after the Bid Boost was initiated by the seller.
Once the seller has activated Bid Boost, each bidder will be notified of the new auction expiry date and time.