Hi Deborah & womandi,
The process that Marcia described will replace any instances of the images in question which appear within the descriptions of your active listings, but will not update any copies of the images that are displayed in the Header/Gallery section on eBay.
If you are using these images as Gallery images as well, you would need to update them there by going to the “Revise your Item” form for the item(s) directly on the eBay website and updating them within the “Add Photos” section.
I hope this clears things up. If you need any more specific assistance with this, please feel free to contact our Customer Support team directly from under the “Help” tab on our site and we will be happy to continue working with you.