As stated by Ebay..................

"Sometimes something goes wrong and you can't complete your listing as planned. If needed, you can choose to end your listing before the scheduled date. If there are bids on your item, you can cancel them."

Reasons for ending listings early include:

The item is no longer available for sale.
There was an error in the starting price or reserve amount.
There was an error in the listing.
The item was lost or broken.

Timing Matters

When there are 12 hours or fewer remaining and the item has a winning bid, including a reserve met bid, sellers may not make any changes to the listing, including:

ending the item early.

Sellers may cancel bids, but not end the item
adding to or changing the item description
converting the item to pre-approved bidder

Canceling bids or making changes to a listing with bids when there are 12 hours or fewer remaining damages the buyer experience and can undermine trust in the marketplace."

So yes you can do it, although not advised.