Hi! I don't know if this will help much, but when I had to be away for several days and needed to alert potential buyers, I updated the message on my Scrolling Gallery. The new message will appear in your gallery within a couple of hours. It's not the best solution, but it is an easy way to get a message to your buyers on every listing without all the hassle of trying to edit each one on eBay!
(Stores tab>Edit Scrolling Gallery>edit Text & Placement>put new message in the Gallery Title)
Good luck and have a great holiday!