Vacation Mode allows you to pause your active Asks when you know you'll be away and unable to ship your items in the event of a sale. While this won't cancel sales that are already in progress, this mode allows you to pause your Asks that haven't yet matched with a Bid until you're ready to sell and ship again.

To enable Vacation Mode, simply navigate to My Account > Settings and click the "Turn on" button under "Vacation Mode" in the Seller Info section. Remember that once enabled, you'll have to manually turn Vacation Mode off again before your Asks will be active on the site. 
 

A highlight with activating Vacation Mode while you’re away is that you can end up with an automatic sale if your item spikes in popularity with bids above your asking price while Vacation Mode is enabled. When you turn Vacation Mode off your item will immediately sell. However, not at the highest Bid but for your Ask as this is what you had your item listed for before activating Vacation Mode. If you are afraid of this occurring, to avoid this, we suggest removing/deleting your Asks.